diff --git a/lib/User/AuthClient/Facebook.php b/lib/User/AuthClient/Facebook.php
index 3ccfe8e..1554a3b 100644
--- a/lib/User/AuthClient/Facebook.php
+++ b/lib/User/AuthClient/Facebook.php
@@ -3,8 +3,9 @@
 namespace Da\User\AuthClient;
 
 use Da\User\Contracts\AuthClientInterface;
+use yii\authclient\clients\Facebook as BaseFacebook;
 
-class Facebook extends \yii\authclient\clients\Facebook implements AuthClientInterface
+class Facebook extends BaseFacebook implements AuthClientInterface
 {
     /**
      * {@inheritdoc}
@@ -21,6 +22,6 @@ class Facebook extends \yii\authclient\clients\Facebook implements AuthClientInt
      */
     public function getUsername()
     {
-        return;
+        return null;
     }
 }
diff --git a/lib/User/AuthClient/GitHub.php b/lib/User/AuthClient/GitHub.php
index a0dd7c3..e019972 100644
--- a/lib/User/AuthClient/GitHub.php
+++ b/lib/User/AuthClient/GitHub.php
@@ -3,8 +3,9 @@
 namespace Da\User\AuthClient;
 
 use Da\User\Contracts\AuthClientInterface;
+use yii\authclient\clients\GitHub as BaseGitHub;
 
-class GitHub extends \yii\authclient\clients\GitHub implements AuthClientInterface
+class GitHub extends BaseGitHub implements AuthClientInterface
 {
     /**
      * {@inheritdoc}
diff --git a/lib/User/AuthClient/Google.php b/lib/User/AuthClient/Google.php
index 818cac6..1a6b1c5 100644
--- a/lib/User/AuthClient/Google.php
+++ b/lib/User/AuthClient/Google.php
@@ -3,8 +3,9 @@
 namespace Da\User\AuthClient;
 
 use Da\User\Contracts\AuthClientInterface;
+use yii\authclient\clients\Google as BaseGoogle;
 
-class Google extends \yii\authclient\clients\Google implements AuthClientInterface
+class Google extends BaseGoogle implements AuthClientInterface
 {
     /**
      * {@inheritdoc}
@@ -21,6 +22,6 @@ class Google extends \yii\authclient\clients\Google implements AuthClientInterfa
      */
     public function getUsername()
     {
-        return;
+        return null;
     }
 }
diff --git a/lib/User/AuthClient/LinkedIn.php b/lib/User/AuthClient/LinkedIn.php
index 04177a0..bdd1f8f 100644
--- a/lib/User/AuthClient/LinkedIn.php
+++ b/lib/User/AuthClient/LinkedIn.php
@@ -3,8 +3,9 @@
 namespace Da\User\AuthClient;
 
 use Da\User\Contracts\AuthClientInterface;
+use yii\authclient\clients\LinkedIn as BaseLinkedIn;
 
-class LinkedIn extends \yii\authclient\clients\LinkedIn implements AuthClientInterface
+class LinkedIn extends BaseLinkedIn implements AuthClientInterface
 {
     /**
      * {@inheritdoc}
@@ -21,6 +22,6 @@ class LinkedIn extends \yii\authclient\clients\LinkedIn implements AuthClientInt
      */
     public function getUsername()
     {
-        return;
+        return null;
     }
 }
diff --git a/lib/User/AuthClient/Twitter.php b/lib/User/AuthClient/Twitter.php
index 23c013f..35d6dbd 100644
--- a/lib/User/AuthClient/Twitter.php
+++ b/lib/User/AuthClient/Twitter.php
@@ -3,8 +3,9 @@
 namespace Da\User\AuthClient;
 
 use Da\User\Contracts\AuthClientInterface;
+use yii\authclient\clients\Twitter as BaseTwitter;
 
-class Twitter extends \yii\authclient\clients\Twitter implements AuthClientInterface
+class Twitter extends BaseTwitter implements AuthClientInterface
 {
     /**
      * @return string
diff --git a/lib/User/AuthClient/VKontakte.php b/lib/User/AuthClient/VKontakte.php
index 2268e80..3cfad1c 100644
--- a/lib/User/AuthClient/VKontakte.php
+++ b/lib/User/AuthClient/VKontakte.php
@@ -4,8 +4,9 @@ namespace Da\User\AuthClient;
 
 use Da\User\Contracts\AuthClientInterface;
 use Yii;
+use yii\authclient\clients\VKontakte as BaseVKontakte;
 
-class VKontakte extends \yii\authclient\clients\VKontakte implements AuthClientInterface
+class VKontakte extends BaseVKontakte implements AuthClientInterface
 {
     /**
      * {@inheritdoc}
diff --git a/lib/User/AuthClient/Yandex.php b/lib/User/AuthClient/Yandex.php
index 3ae4654..ff8a24b 100644
--- a/lib/User/AuthClient/Yandex.php
+++ b/lib/User/AuthClient/Yandex.php
@@ -4,8 +4,9 @@ namespace Da\User\AuthClient;
 
 use Da\User\Contracts\AuthClientInterface;
 use Yii;
+use yii\authclient\clients\Yandex as BaseYandex;
 
-class Yandex extends \yii\authclient\clients\Yandex implements AuthClientInterface
+class Yandex extends BaseYandex implements AuthClientInterface
 {
     /**
      * {@inheritdoc}
diff --git a/lib/User/Command/ConfirmController.php b/lib/User/Command/ConfirmController.php
index 38f29ef..6fa32d1 100644
--- a/lib/User/Command/ConfirmController.php
+++ b/lib/User/Command/ConfirmController.php
@@ -5,9 +5,9 @@ namespace Da\User\Command;
 use Da\User\Query\UserQuery;
 use Da\User\Service\UserConfirmationService;
 use Da\User\Traits\ContainerTrait;
+use Yii;
 use yii\base\Module;
 use yii\console\Controller;
-use Yii;
 use yii\helpers\Console;
 
 class ConfirmController extends Controller
diff --git a/lib/User/Command/CreateController.php b/lib/User/Command/CreateController.php
index c048756..5c30439 100644
--- a/lib/User/Command/CreateController.php
+++ b/lib/User/Command/CreateController.php
@@ -6,8 +6,8 @@ use Da\User\Factory\MailFactory;
 use Da\User\Model\User;
 use Da\User\Service\UserCreateService;
 use Da\User\Traits\ContainerTrait;
-use yii\console\Controller;
 use Yii;
+use yii\console\Controller;
 use yii\helpers\Console;
 
 class CreateController extends Controller