Websocket 报错

全部按照文章配置后，网页可以正常打开。但是websocket连接的时候要报错。请问这个可能是啥原因造成的。

root@fbde3b60aded:/var/www/Pang# php artisan swoole:http start
Starting swoole http server...
Swoole http server started: <http://workspace:1215>
ErrorException: Swoole\WebSocket\Server::push(): the connected client of connection[4] is not a websocket client or closed in /var/www/Pang/vendor/swooletw/laravel-swoole/src/Websocket/SocketIO/WebsocketHandler.php:36
Stack trace:
#0 [internal function]: Illuminate\Foundation\Bootstrap\HandleExceptions->handleError(2, 'Swoole\\WebSocke...', '/var/www/Pang/v...', 36, Array)
#1 /var/www/Pang/vendor/swooletw/laravel-swoole/src/Websocket/SocketIO/WebsocketHandler.php(36): Swoole\WebSocket\Server->push(4, '0{"sid":"NWRhNT...')
#2 /var/www/Pang/vendor/swooletw/laravel-swoole/src/Concerns/InteractsWithWebsocket.php(95): SwooleTW\Http\Websocket\SocketIO\WebsocketHandler->onOpen(4, Object(Illuminate\Http\Request))
#3 {main}

root@fbde3b60aded:/var/www/Pang# php artisan swoole:http infos