diff --git a/src/DependencyInjection/ServiceContainer.php b/src/DependencyInjection/ServiceContainer.php
index 9e4d61f..28b2d23 100644
--- a/src/DependencyInjection/ServiceContainer.php
+++ b/src/DependencyInjection/ServiceContainer.php
@@ -19,7 +19,7 @@ public function getContainerBuilder(): ContainerBuilder
         $loader = new YamlFileLoader($containerBuilder, new FileLocator(__DIR__ . '/../../src/config'));
         $loader->load('services.yaml');
 
-        $containerBuilder->setParameter('FILE_NAME', $_ENV['FILE_NAME']);
+        $containerBuilder->setParameter('STORED_HASH_FILE', $_ENV['STORED_HASH_FILE']);
 
         return $containerBuilder;
     }
diff --git a/src/Validator/FileValidatorTrait.php b/src/Validator/FileValidatorTrait.php
index 33e3f61..7292dc7 100644
--- a/src/Validator/FileValidatorTrait.php
+++ b/src/Validator/FileValidatorTrait.php
@@ -17,10 +17,10 @@ public function validateFileName(string $filename, string|null $path = null): st
     {
         $container = (new ServiceContainer())->getContainerBuilder();
 
-        $stored_hash_file = $container->getParameter('FILE_NAME');
+        $stored_hash_file = $container->getParameter('STORED_HASH_FILE');
 
         if ($filename != $stored_hash_file) {
-            self::sanitize($filename);
+            $this->sanitize($filename);
         }
 
 
diff --git a/tests/Base/BaseTest.php b/tests/Base/BaseTest.php
index a8e5cea..4d98fef 100644
--- a/tests/Base/BaseTest.php
+++ b/tests/Base/BaseTest.php
@@ -13,7 +13,7 @@ class BaseTest extends TestCase
      */
     protected static array|null $files = [];
 
-    private static ContainerBuilder|null $containerBuilder;
+    protected static ContainerBuilder|null $containerBuilder;
 
     public static function setUpBeforeClass(): void
     {
diff --git a/tests/unit/FileHashCheckerTest.php b/tests/unit/FileHashCheckerTest.php
index 64d3566..ee8c8c2 100644
--- a/tests/unit/FileHashCheckerTest.php
+++ b/tests/unit/FileHashCheckerTest.php
@@ -4,8 +4,9 @@
 
 use Base\BaseTest;
 use PHPUnit\Framework\Attributes\Test;
+use Rcsofttech85\FileHandler\Exception\FileHandlerException;
+use Rcsofttech85\FileHandler\Exception\HashException;
 use Rcsofttech85\FileHandler\FileHashChecker;
-use Symfony\Component\Dotenv\Dotenv;
 
 class FileHashCheckerTest extends BaseTest
 {
@@ -29,10 +30,11 @@ protected function tearDown(): void
     public static function setUpBeforeClass(): void
     {
         parent::setUpBeforeClass();
-        $dotenv = new Dotenv();
-        $dotenv->load('.env');
 
-        self::$file = $_ENV['FILE_NAME'];
+        $file = self::$containerBuilder->getParameter('STORED_HASH_FILE');
+        if (is_string($file)) {
+            self::$file = $file;
+        }
         static::$files = ['movie.csv', 'sample'];
     }
 
@@ -41,6 +43,10 @@ public static function tearDownAfterClass(): void
         parent::tearDownAfterClass();
     }
 
+
+    /**
+     * @throws HashException
+     */
     #[Test]
     public function shouldGenerateValidHashForDifferentAlgo(): void
     {
@@ -58,6 +64,10 @@ public function shouldGenerateValidHashForDifferentAlgo(): void
         $this->assertEquals($expectedHash, $actualHash);
     }
 
+    /**
+     * @throws HashException
+     * @throws FileHandlerException
+     */
     #[Test]
     public function checkFileIntegrityReturnsTrueIfHashMatch(): void
     {
@@ -66,6 +76,10 @@ public function checkFileIntegrityReturnsTrueIfHashMatch(): void
         $this->assertTrue($isVerified);
     }
 
+    /**
+     * @throws HashException
+     * @throws FileHandlerException
+     */
     #[Test]
     public function shouldReturnFalseIfFileIsModified(): void
     {
@@ -79,6 +93,10 @@ public function shouldReturnFalseIfFileIsModified(): void
         file_put_contents("movie.csv", $backup);
     }
 
+    /**
+     * @throws HashException
+     * @throws FileHandlerException
+     */
     #[Test]
     public function shouldReturnFalseIfDifferentAlgoIsUsedForVerifyHash(): void
     {