Laravel Queue

#0 [internal function]: PDO->__sleep()
#1 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Queue/Queue.php(128): serialize(Object(Illuminate\Broadcasting\BroadcastEvent))
#2 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Queue/Queue.php(108): Illuminate\Queue\Queue->createObjectPayload(Object(Illuminate\Broadcasting\BroadcastEvent))
#3 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Queue/Queue.php(87): Illuminate\Queue\Queue->createPayloadArray(Object(Illuminate\Broadcasting\BroadcastEvent), '')
#4 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Queue/DatabaseQueue.php(82): Illuminate\Queue\Queue->createPayload(Object(Illuminate\Broadcasting\BroadcastEvent), '')
#5 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Queue/Queue.php(44): Illuminate\Queue\DatabaseQueue->push(Object(Illuminate\Broadcasting\BroadcastEvent), '', NULL)
#6 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Broadcasting/BroadcastManager.php(125): Illuminate\Queue\Queue->pushOn(NULL, Object(Illuminate\Broadcasting\BroadcastEvent))
#7 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Events/Dispatcher.php(271): Illuminate\Broadcasting\BroadcastManager->queue(Object(App\Events\NewTask))
#8 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Events/Dispatcher.php(194): Illuminate\Events\Dispatcher->broadcastEvent(Object(App\Events\NewTask))
#9 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Broadcasting/PendingBroadcast.php(57): Illuminate\Events\Dispatcher->dispatch('App\\Events\\NewT...')
#10 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Foundation/helpers.php(209): Illuminate\Broadcasting\PendingBroadcast->__destruct()
#11 /var/www/html/username/app/Http/Controllers/CServerController.php(146): broadcast(Object(App\Events\NewTask))
#12 [internal function]: App\Http\Controllers\CServerController->upload(Object(Illuminate\Http\Request))
#13 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Controller.php(54): call_user_func_array(Array, Array)
#14 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php(45): Illuminate\Routing\Controller->callAction('upload', Array)
#15 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Route.php(212): Illuminate\Routing\ControllerDispatcher->dispatch(Object(Illuminate\Routing\Route), Object(App\Http\Controllers\CServerController), 'upload')
#16 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Route.php(169): Illuminate\Routing\Route->runController()
#17 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Router.php(658): Illuminate\Routing\Route->run()
#18 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(30): Illuminate\Routing\Router->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#19 /var/www/html/username/app/Http/Middleware/TrackApiCalls.php(31): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#20 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(149): App\Http\Middleware\TrackApiCalls->handle(Object(Illuminate\Http\Request), Object(Closure))
#21 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}(Object(Illuminate\Http\Request))
#22 /var/www/html/username/app/Http/Middleware/VerifyClientKey.php(32): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#23 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(149): App\Http\Middleware\VerifyClientKey->handle(Object(Illuminate\Http\Request), Object(Closure))
#24 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}(Object(Illuminate\Http\Request))
#25 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Middleware/SubstituteBindings.php(41): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#26 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(149): Illuminate\Routing\Middleware\SubstituteBindings->handle(Object(Illuminate\Http\Request), Object(Closure))
#27 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}(Object(Illuminate\Http\Request))
#28 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Middleware/ThrottleRequests.php(57): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#29 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(149): Illuminate\Routing\Middleware\ThrottleRequests->handle(Object(Illuminate\Http\Request), Object(Closure), 60, '1')
#30 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}(Object(Illuminate\Http\Request))
#31 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(102): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#32 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Router.php(660): Illuminate\Pipeline\Pipeline->then(Object(Closure))
#33 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Router.php(635): Illuminate\Routing\Router->runRouteWithinStack(Object(Illuminate\Routing\Route), Object(Illuminate\Http\Request))
#34 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Router.php(601): Illuminate\Routing\Router->runRoute(Object(Illuminate\Http\Request), Object(Illuminate\Routing\Route))
#35 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Router.php(590): Illuminate\Routing\Router->dispatchToRoute(Object(Illuminate\Http\Request))
#36 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(176): Illuminate\Routing\Router->dispatch(Object(Illuminate\Http\Request))
#37 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(30): Illuminate\Foundation\Http\Kernel->Illuminate\Foundation\Http\{closure}(Object(Illuminate\Http\Request))
#38 /var/www/html/username/vendor/barryvdh/laravel-debugbar/src/Middleware/InjectDebugbar.php(65): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#39 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(149): Barryvdh\Debugbar\Middleware\InjectDebugbar->handle(Object(Illuminate\Http\Request), Object(Closure))
#40 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}(Object(Illuminate\Http\Request))
#41 /var/www/html/username/vendor/fideloper/proxy/src/TrustProxies.php(56): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#42 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(149): Fideloper\Proxy\TrustProxies->handle(Object(Illuminate\Http\Request), Object(Closure))
#43 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}(Object(Illuminate\Http\Request))
#44 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(30): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))
#45 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(149): Illuminate\Foundation\Http\Middleware\TransformsRequest->handle(Object(Illuminate\Http\Request), Object(Closure))
#46 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}(Object(Illuminate\Http\Request))
#47 /var/www/html/username/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(30): Illuminate\Routing\Pipeline->Illuminate\Routing\{closure}(Object(Illuminate\Http\Request))

broadcast(new NewTask($newTask));

NEW TASK.php

<?php

namespace App\Events;

//use App\Task;
use Illuminate\Broadcasting\Channel;
use Illuminate\Queue\SerializesModels;
use Illuminate\Broadcasting\PrivateChannel;
use Illuminate\Broadcasting\PresenceChannel;
use Illuminate\Foundation\Events\Dispatchable;
use Illuminate\Broadcasting\InteractsWithSockets;
use Illuminate\Contracts\Broadcasting\ShouldBroadcast;

class NewTask implements ShouldBroadcast
{
    use Dispatchable, InteractsWithSockets, SerializesModels;

    
    public $task;

    /**
     * Create a new event instance.
     *
     * @return void
     */
    public function __construct($task)
    {
        $this->task = $task;
    }

    /**
     * Get the channels the event should broadcast on.
     *
     * @return \Illuminate\Broadcasting\Channel|array
     */
    public function broadcastOn()
    {
        return new Channel('tasks');
    }


    public function broadcastWith()
    {

        return [ 
            'id' => $this->task->id,
            'callback_url' => $this->task->callback_url,
            'client_id' => $this->task->client_id,
            'client' => $this->task->client,
            'created_at' => $this->task->created_at,
            'input' => $this->task->input,
            'length' => $this->task->length,
            'provider' => $this->task->provider,
            'ref_key' => $this->task->ref_key,
            'retries' => $this->task->retries,
            'request_time' => $this->task->request_time,
            'show_status' => $this->task->showStatus,
            'status' => $this->task->status,
            'transcripts' => $this->task->transcripts,
            'type' => $this->task->type,
            ///'user' => $this->task->user,
        ];
    }
}

I get this error whenever I make a broadcast. Please how can I fix this error..