update configuration

config/mail.php

@@ -82,6 +82,13 @@ return [
             ],
         ],
 
+        'mailgun' => [
+            'domain' => env('MAILGUN_DOMAIN'),
+            'secret' => env('MAILGUN_SECRET'),
+            'endpoint' => env('MAILGUN_ENDPOINT', 'api.mailgun.net'),
+            'scheme' => 'https',
+        ],
+
     ],
 
     /*