I have tried your code it looks perfect but not able to hit api i don't know the issue please take a look

[SameerKhan1406]

Login Activity
package name

import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.text.Html;
import android.text.method.LinkMovementMethod;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;


import org.json.JSONException;
import org.json.JSONObject;

import java.util.HashMap;
import java.util.Map;

public class LoginActivity extends BaseActivity implements View.OnClickListener {

    private static String TAG = LoginActivity.class.getSimpleName();

    private PrefManager pref;
    private Button mLoginButton,btnRequestSms;
    private EditText mLoginNo,inputOtp;
    private ProgressDialog mSpinner;
    private CheckBox mBox;
    private SQLiteDatabase db;
    private TextView otptext;



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        createDatabase();
        mBox = (CheckBox) findViewById(R.id.checkBox1);
        otptext= (TextView) findViewById(R.id.otptext);
        inputOtp=(EditText) findViewById(R.id.inputOtp);
        String checkBoxText = "I agree to all the <a href='http://www.redbus.in/mob/mTerms.aspx' > Terms and Conditions</a>";

        mBox.setText(Html.fromHtml(checkBoxText));
        pref = new PrefManager(this);
        mBox.setMovementMethod(LinkMovementMethod.getInstance());
        btnRequestSms = (Button) findViewById(R.id.btn_request_sms);
        mLoginButton = (Button) findViewById(R.id.loginButton);
        mBox.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View view) {
                if(mBox.isChecked()){
                    btnRequestSms.setVisibility(View.VISIBLE);
                }
                else{
                    mLoginButton.setVisibility(View.GONE);
                    btnRequestSms.setVisibility(View.GONE);
                    otptext.setVisibility(View.GONE);
                    inputOtp.setVisibility(View.GONE);
                }
            }
        });
        ;
        btnRequestSms.setOnClickListener((OnClickListener) this);
        mLoginButton.setOnClickListener((OnClickListener) this);
        mLoginNo = (EditText) findViewById(R.id.loginNo);
        mLoginButton.setEnabled(false);
        mLoginButton.setOnClickListener((OnClickListener) this);

        // Checking for user session
        // if user is already logged in, take him to main activity
        if (pref.isLoggedIn()) {
            Intent intent = new Intent(LoginActivity.this, PlaceCallActivity.class);
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TOP);
            startActivity(intent);

            finish();
        }

    }
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.btn_request_sms:
                otptext.setVisibility(View.VISIBLE);
                inputOtp.setVisibility(View.VISIBLE);
                mLoginButton.setVisibility(View.VISIBLE);
                validateForm();
                verifyOtp();
                break;

            case R.id.loginButton:

                loginClicked();
                break;

        }
    }
    protected void createDatabase(){
        db=openOrCreateDatabase("NumberDB", Context.MODE_PRIVATE, null);
        db.execSQL("CREATE TABLE IF NOT EXISTS numbers(id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, number INT(4));");
    }
    protected void insertIntoDB(){
        String number = mLoginNo.getText().toString();
        if(number.equals("")){
            Toast.makeText(getApplicationContext(),"Please fill all fields", Toast.LENGTH_LONG).show();
            return;
        }

        String query = "INSERT INTO persons (name,address) VALUES("+number+");";
        db.execSQL(query);
        Toast.makeText(getApplicationContext(),"Saved Successfully", Toast.LENGTH_LONG).show();
    }

    @Override
    protected void onPause() {
        if (mSpinner != null) {
            mSpinner.dismiss();
        }
        super.onPause();
    }

    @Override
    public void onStartFailed(SinchError error) {
        Toast.makeText(this, error.toString(), Toast.LENGTH_LONG).show();
        if (mSpinner != null) {
            mSpinner.dismiss();
        }
    }

    @Override
    public void onStarted() {
        openPlaceCallActivity();
    }

    private void loginClicked() {
        String userNo = mLoginNo.getText().toString();

        if (userNo.isEmpty()) {
            Toast.makeText(this, "Please enter your number", Toast.LENGTH_LONG).show();
            return;
        }
    }

    private void showSpinner() {
        mSpinner = new ProgressDialog(this);
        mSpinner.setTitle("Logging in");
        mSpinner.setMessage("Please wait...");
        mSpinner.show();
    }

    private void validateForm() {

        String mobile = mLoginNo.getText().toString().trim();

        // validating mobile number
        // it should be of 10 digits length
        if (isValidPhoneNumber(mobile)) {

            // saving the mobile number in shared preferences
            pref.setMobileNumber(mobile);

            // requesting for sms
            requestForSMS(mobile);

        } else {
            Toast.makeText(getApplicationContext(), "Please enter valid mobile number", Toast.LENGTH_SHORT).show();
        }
    }


    private void requestForSMS(final String mobile) {
        StringRequest strReq = new StringRequest(Request.Method.POST,
                Config.URL_REQUEST_SMS, new Response.Listener<String>() {

            @Override
            public void onResponse(String response) {
                Log.d(TAG, response.toString());

                try {
                    JSONObject responseObj = new JSONObject(response);

                    // Parsing json object response
                    // response will be a json object
                    boolean error = responseObj.getBoolean("error");
                    String message = responseObj.getString("message");

                    // checking for error, if not error SMS is initiated
                    // device should receive it shortly
                    if (!error) {
                        // boolean flag saying device is waiting for sms
                        pref.setIsWaitingForSms(true);

                        Toast.makeText(getApplicationContext(), message, Toast.LENGTH_SHORT).show();

                    } else {
                        Toast.makeText(getApplicationContext(),
                                "Error: " + message,
                                Toast.LENGTH_LONG).show();
                    }

                    // hiding the progress bar


                } catch (JSONException e) {
                    Toast.makeText(getApplicationContext(),
                            "Error: " + e.getMessage(),
                            Toast.LENGTH_LONG).show();


                }

            }
        }, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {
                Log.e(TAG, "Error: " + error.getMessage());
                Toast.makeText(getApplicationContext(),
                        error.getMessage(), Toast.LENGTH_SHORT).show();
            }
        }) {

            /**
             * Passing user parameters to our server
             * @return
             */
            @Override
            protected Map<String, String> getParams() {
                Map<String, String> params = new HashMap<String, String>();
                params.put("mobile", mobile);

                Log.e(TAG, "Posting params: " + params.toString());

                return params;
            }

        };

        // Adding request to request queue
        MyApplication.getInstance().addToRequestQueue(strReq);
    }

    /**
     * sending the OTP to server and activating the user
     */







    private void verifyOtp() {
        String otp = inputOtp.getText().toString().trim();

        if (!otp.isEmpty()) {
            Intent grapprIntent = new Intent(getApplicationContext(), HttpService.class);
            grapprIntent.putExtra("otp", otp);
            startService(grapprIntent);
        } else {
            Toast.makeText(getApplicationContext(), "Please enter the OTP", Toast.LENGTH_SHORT).show();
        }
    }

    /**
     * Regex to validate the mobile number
     * mobile number should be of 10 digits length
     *
     * @param mobile
     * @return
     */


    private static boolean isValidPhoneNumber(String mobile) {
        String regEx = "^[0-9]{10}$";
        return mobile.matches(regEx);
    }
   
}

Login xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="0dip"
    tools:context=".LoginActivity">

    <RelativeLayout
        android:id="@+id/layout_sms"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <ImageView android:src="@drawable/bg"
            android:layout_width="150dp"
            android:layout_height="150dp"
            android:layout_marginTop="40dp"
            android:adjustViewBounds="true"
            android:layout_centerHorizontal="true"
            />


        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            android:paddingLeft="40dp"
            android:paddingRight="40dp"
            android:id="@+id/linearLayout">

            <TextView
                android:id="@+id/textView"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center_horizontal"
                android:layout_marginTop="200dp"
                android:text="Enter your Mobile No"
                android:textAllCaps="true"
                android:textColor="@color/purple"
                android:textSize="20sp" />

            <EditText
                android:id="@+id/loginNo"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginTop="8dp"
                android:background="@drawable/inputbox"
                android:digits="1234567890"
                android:inputType="phone"
                android:padding="10dp"
                android:textColor="@color/purple"
                android:textSize="25sp"
                android:maxLength="10">

                <requestFocus />
            </EditText>

        </LinearLayout>

        <Button
            android:id="@+id/btn_request_sms"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_centerHorizontal="true"
            android:layout_gravity="center_horizontal"
            android:layout_marginBottom="210dp"
            android:text="NEXT"
            android:background="@color/btnclr"
            android:minHeight="30dp"
            android:minWidth="150dp"
            android:textColor="@color/off_white"
            android:textSize="14dp"
            android:textStyle="bold"
            android:visibility="gone" />



        <CheckBox
            android:id="@+id/checkBox1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_centerHorizontal="true"
            android:layout_marginBottom="20dp"
            android:textColor="@color/black"
            android:buttonTint="@color/black"/>
        </RelativeLayout>

        <LinearLayout
            android:id="@+id/layout_otp"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:gravity="center_horizontal"
            android:orientation="vertical"
            android:layout_marginTop="350dp"
            >

            <TextView
                android:id="@+id/otptext"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:layout_marginBottom="10dp"
                android:gravity="center_horizontal"
                android:paddingLeft="40dp"
                android:paddingRight="40dp"
                android:text="@string/msg_manual_otp"
                android:textColor="@android:color/black"
                android:textSize="12dp"
                android:visibility="gone"/>

            <EditText
                android:id="@+id/inputOtp"
                android:layout_width="120dp"
                android:layout_height="wrap_content"
                android:background="@drawable/inputbox"
                android:fontFamily="sans-serif-light"
                android:gravity="center_horizontal"
                android:hint="@string/lbl_enter_otp"
                android:inputType="number"
                android:maxLength="6"
                android:padding="10dp"
                android:textCursorDrawable="@null"
                android:textSize="18dp"
                android:layout_marginTop="10dp"
                android:visibility="gone"/>
            <Button
                android:id="@+id/loginButton"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentBottom="true"
                android:layout_centerHorizontal="true"
                android:layout_gravity="center_horizontal"
                android:layout_marginTop="15dp"
                android:text="VERIFY"
                android:background="@color/btnclr"
                android:minHeight="30dp"
                android:minWidth="150dp"
                android:textColor="@color/off_white"
                android:textSize="14dp"
                android:textStyle="bold"
                android:visibility="gone" />

        </LinearLayout>


</RelativeLayout>

[SameerKhan1406]

in Android Monitor i am getting this
11-08 15:12:25.835 19058-19301/appid E/LoginActivity: Posting params: {mobile=7704052254}
11-08 15:12:25.845 19058-19301/appid D/libc-netbsd: [getaddrinfo]: hostname=192.168.0.19; servname=(null); cache_mode=(null), netid=0; mark=0
11-08 15:12:25.846 19058-19301/appid D/libc-netbsd: [getaddrinfo]: ai_addrlen=0; ai_canonname=(null); ai_flags=4; ai_family=0
11-08 15:12:25.847 19058-19301/appid D/libc-netbsd: [getaddrinfo]: hostname=192.168.0.19; servname=(null); cache_mode=(null), netid=0; mark=0
11-08 15:12:25.847 19058-19301/appid D/libc-netbsd: [getaddrinfo]: ai_addrlen=0; ai_canonname=(null); ai_flags=4; ai_family=0
11-08 15:12:25.849 19058-19301/appid I/System.out: [CDS]rx timeout:2500
11-08 15:12:25.850 19058-19301/appid I/System.out: [socket][2] connection /192.168.0.19:80;LocalPort=41088(2500)
11-08 15:12:25.850 19058-19301/appid I/System.out: [CDS]connect[/192.168.0.19:80] tm:2
11-08 15:12:25.853 19058-19301/appid D/Posix: [Posix_connect Debug]Process com.medmainfomatix.form :80
11-08 15:12:25.910 19058-19085/appid D/GraphicBuffer: register, handle(0xb7915ab8) (w:275 h:66 s:288 f:0x1 u:0x000f02)
11-08 15:12:25.911 19058-19085/appid I/MaliEGL: [Mali]window_type=1, is_framebuffer=0, errnum = 0
11-08 15:12:25.911 19058-19085/appid I/MaliEGL: [Mali]surface->num_buffers=4, surface->num_frames=3, win_min_undequeued=1
11-08 15:12:25.911 19058-19085/appid I/MaliEGL: [Mali]max_allowed_dequeued_buffers=3
11-08 15:12:25.912 19058-19085/appid D/GraphicBuffer: unregister, handle(0xb7915ab8) (w:275 h:66 s:288 f:0x1 u:0x000f02)
11-08 15:12:25.914 19058-19085/appid D/GraphicBuffer: register, handle(0xb7915ab8) (w:275 h:66 s:288 f:0x1 u:0x000f02)
11-08 15:12:27.843 19058-19085/appid D/OpenGLRenderer: Flushing caches (mode 0)
11-08 15:12:27.843 19058-19085/appid D/OpenGLRenderer: Flushing caches (mode 0)
11-08 15:12:27.843 19058-19085/appid D/GraphicBuffer: unregister, handle(0xb7915ab8) (w:275 h:66 s:288 f:0x1 u:0x000f02)
11-08 15:12:28.356 19058-19301/com.medmainfomatix.form I/System.out: [socket][3:41088] exception
11-08 15:12:28.358 19058-19301/appid I/System.out: [CDS]close[41088]
11-08 15:12:28.360 19058-19301/appid E/LoginActivity: Posting params: {mobile=7704052254}
11-08 15:12:28.361 19058-19301/appid D/libc-netbsd: [getaddrinfo]: hostname=192.168.0.19; servname=(null); cache_mode=(null), netid=0; mark=0
11-08 15:12:28.361 19058-19301/appid D/libc-netbsd: [getaddrinfo]: ai_addrlen=0; ai_canonname=(null); ai_flags=4; ai_family=0
11-08 15:12:28.362 19058-19301/appid D/libc-netbsd: [getaddrinfo]: hostname=192.168.0.19; servname=(null); cache_mode=(null), netid=0; mark=0
11-08 15:12:28.362 19058-19301/appid D/libc-netbsd: [getaddrinfo]: ai_addrlen=0; ai_canonname=(null); ai_flags=4; ai_family=0
11-08 15:12:28.365 19058-19301/appid I/System.out: [CDS]rx timeout:5000
11-08 15:12:28.365 19058-19301/appid I/System.out: [socket][3] connection /192.168.0.19:80;LocalPort=44276(5000)
11-08 15:12:28.366 19058-19301/appid I/System.out: [CDS]connect[/192.168.0.19:80] tm:5
11-08 15:12:28.368 19058-19301/appid D/Posix: [Posix_connect Debug]Process com.medmainfomatix.form :80
11-08 15:12:33.379 19058-19301/appid I/System.out: [socket][4:44276] exception
11-08 15:12:33.380 19058-19301/appid I/System.out: [CDS]close[44276]
11-08 15:12:33.382 19058-19058/appid E/LoginActivity: Error: null
11-08 15:12:33.391 19058-19058/appid D/Volley: [1] Request.finish: 7557 ms: [ ] http://192.168.0.19/myname/AndroidOtp/request_sms.php 0x6768b565 NORMAL 2
11-08 15:12:33.484 19058-19085/appid D/GraphicBuffer: register, handle(0xb78f4920) (w:78 h:66 s:80 f:0x1 u:0x000f02)
11-08 15:12:33.485 19058-19085/appid I/MaliEGL: [Mali]window_type=1, is_framebuffer=0, errnum = 0
11-08 15:12:33.487 19058-19085/appid I/MaliEGL: [Mali]surface->num_buffers=4, surface->num_frames=3, win_min_undequeued=1
11-08 15:12:33.488 19058-19085/appid I/MaliEGL: [Mali]max_allowed_dequeued_buffers=3
11-08 15:12:33.490 19058-19085/appid D/GraphicBuffer: unregister, handle(0xb78f4920) (w:78 h:66 s:80 f:0x1 u:0x000f02)
11-08 15:12:33.494 19058-19085/appid D/GraphicBuffer: register, handle(0xb7935898) (w:78 h:66 s:80 f:0x1 u:0x000f02)
11-08 15:12:35.392 19058-19085/appid D/OpenGLRenderer: Flushing caches (mode 0)
11-08 15:12:35.393 19058-19085/appid D/OpenGLRenderer: Flushing caches (mode 0)
11-08 15:12:35.393 19058-19085/appid D/GraphicBuffer: unregister, handle(0xb7935898) (w:78 h:66 s:80 f:0x1 u:0x000f02)
11-08 15:14:37.817 19058-19085/appid D/OpenGLRenderer: Flushing caches (mode 0)
11-08 15:14:37.818 19058-19085/appid D/OpenGLRenderer: Flushing caches (mode 0)