diff --git a/requirements.txt b/requirements.txt
index 0886cbb..41efa2b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-observable>=0.3.1
+observable==0.3.2
 pubnub==4.*
 pycryptodome>=3.4.4
-requests>=2.12.4
\ No newline at end of file
+requests>=2.12.4
diff --git a/ringcentral/http/client.py b/ringcentral/http/client.py
index b8e066c..ef48c46 100644
--- a/ringcentral/http/client.py
+++ b/ringcentral/http/client.py
@@ -62,12 +62,13 @@ def create_request(self, method='', url='', query_params=None, body=None, header
         if query_params:
             if type(query_params) is dict:
                 query = ""
-                for key, value in query_params.iteritems():
+                for key, value in  iter(query_params.items()):
                     if type(value) is list:
                         for k in value:
-                            query += ("%s=%s&" % (key, urllib.quote_plus(k)))
+                            query += ("%s=%s&" % (key, k))
                     else:
-                        query += ("%s=%s&" % (key, urllib.quote_plus(value)))
+                        query += ("%s=%s&" % (key, value))
+                query = query[:-1]
             else:
                 query = urlencode(query_params)
             if query: