diff --git a/modules/openapi-generator/src/main/resources/php-nextgen/ObjectSerializer.mustache b/modules/openapi-generator/src/main/resources/php-nextgen/ObjectSerializer.mustache
index fa0589892fbe..5efe3ede3a50 100644
--- a/modules/openapi-generator/src/main/resources/php-nextgen/ObjectSerializer.mustache
+++ b/modules/openapi-generator/src/main/resources/php-nextgen/ObjectSerializer.mustache
@@ -579,6 +579,6 @@ class ObjectSerializer
             }
         }
 
-        return $qs ? (string) substr($qs, 0, -1) : '';
+        return $qs ? substr($qs, 0, -1) : '';
     }
 }
diff --git a/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache b/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache
index 779c750aeb12..7c912fcae611 100644
--- a/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache
+++ b/modules/openapi-generator/src/main/resources/php/ObjectSerializer.mustache
@@ -586,6 +586,6 @@ class ObjectSerializer
             }
         }
 
-        return $qs ? (string) substr($qs, 0, -1) : '';
+        return $qs ? substr($qs, 0, -1) : '';
     }
 }
diff --git a/samples/client/echo_api/php-nextgen-streaming/src/ObjectSerializer.php b/samples/client/echo_api/php-nextgen-streaming/src/ObjectSerializer.php
index 5ebe34b492a4..f984630d55a9 100644
--- a/samples/client/echo_api/php-nextgen-streaming/src/ObjectSerializer.php
+++ b/samples/client/echo_api/php-nextgen-streaming/src/ObjectSerializer.php
@@ -588,6 +588,6 @@ public static function buildQuery(array $params, $encoding = PHP_QUERY_RFC3986):
             }
         }
 
-        return $qs ? (string) substr($qs, 0, -1) : '';
+        return $qs ? substr($qs, 0, -1) : '';
     }
 }
diff --git a/samples/client/echo_api/php-nextgen/src/ObjectSerializer.php b/samples/client/echo_api/php-nextgen/src/ObjectSerializer.php
index 5ebe34b492a4..f984630d55a9 100644
--- a/samples/client/echo_api/php-nextgen/src/ObjectSerializer.php
+++ b/samples/client/echo_api/php-nextgen/src/ObjectSerializer.php
@@ -588,6 +588,6 @@ public static function buildQuery(array $params, $encoding = PHP_QUERY_RFC3986):
             }
         }
 
-        return $qs ? (string) substr($qs, 0, -1) : '';
+        return $qs ? substr($qs, 0, -1) : '';
     }
 }
diff --git a/samples/client/petstore/php-nextgen/OpenAPIClient-php/src/ObjectSerializer.php b/samples/client/petstore/php-nextgen/OpenAPIClient-php/src/ObjectSerializer.php
index fe5558f151b9..3c371f7933f5 100644
--- a/samples/client/petstore/php-nextgen/OpenAPIClient-php/src/ObjectSerializer.php
+++ b/samples/client/petstore/php-nextgen/OpenAPIClient-php/src/ObjectSerializer.php
@@ -587,6 +587,6 @@ public static function buildQuery(array $params, $encoding = PHP_QUERY_RFC3986):
             }
         }
 
-        return $qs ? (string) substr($qs, 0, -1) : '';
+        return $qs ? substr($qs, 0, -1) : '';
     }
 }
diff --git a/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php b/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php
index ee0e9ec22d39..124c526f167f 100644
--- a/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php
+++ b/samples/client/petstore/php/OpenAPIClient-php/lib/ObjectSerializer.php
@@ -594,6 +594,6 @@ public static function buildQuery(array $params, $encoding = PHP_QUERY_RFC3986):
             }
         }
 
-        return $qs ? (string) substr($qs, 0, -1) : '';
+        return $qs ? substr($qs, 0, -1) : '';
     }
 }
diff --git a/samples/client/petstore/php/psr-18/lib/ObjectSerializer.php b/samples/client/petstore/php/psr-18/lib/ObjectSerializer.php
index ee0e9ec22d39..124c526f167f 100644
--- a/samples/client/petstore/php/psr-18/lib/ObjectSerializer.php
+++ b/samples/client/petstore/php/psr-18/lib/ObjectSerializer.php
@@ -594,6 +594,6 @@ public static function buildQuery(array $params, $encoding = PHP_QUERY_RFC3986):
             }
         }
 
-        return $qs ? (string) substr($qs, 0, -1) : '';
+        return $qs ? substr($qs, 0, -1) : '';
     }
 }