Fatal error: Uncaught RuntimeException: Failed to listen on "tcp://0.0.0.0:9001": Address already in use (EADDRINUSE) in /home/developer/public_html/dev.elnashra.com/vendor/react/socket/src/TcpServer.php:188 Stack trace: #0 /home/developer/public_html/dev.elnashra.com/vendor/react/socket/src/Server.php(81): React\Socket\TcpServer->__construct('tcp://0.0.0.0:9...', Object(React\EventLoop\StreamSelectLoop), Array) #1 /home/developer/public_html/dev.elnashra.com/vendor/ratchet/rfc6455/tests/ab/startServer.php(15): React\Socket\Server->__construct('0.0.0.0:9001', Object(React\EventLoop\StreamSelectLoop)) #2 {main} thrown in /home/developer/public_html/dev.elnashra.com/vendor/react/socket/src/TcpServer.php on line 188