Laravel 5.5 Queue Issue

Code Executed in UserController.php:
public function sendEmail(Request $request)
{
    $users = User::all();
    SendEmailUpdates::dispatch($users,request('subject'),request('message'));

    request()->session()->flash('status_success',"E-mail updates has been queued!");
    return back();
}

** App\Jobs\SendEmailUpdates.php **
<?php

namespace App\Jobs;

Use Mail;
use App\Mail\EmailUpdate;
use Illuminate\Bus\Queueable;
use Illuminate\Queue\SerializesModels;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;

class SendEmailUpdates implements ShouldQueue
{
    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;

    protected $users;
    protected $subject;
    protected $message;
    /**
     * Create a new job instance.
     *
     * @return void
     */
    public function __construct($users,$subject,$message)
    {
        $this->users = $users;
        $this->subject = $subject;
        $this->message = $message;
    }

    /**
     * Execute the job.
     *
     * @return void
     */
    public function handle()
    {
        try{
            foreach($this->users as $user){
                Mail::to($user)->send(New EmailUpdate($user,$this->subject,$this->message));
            }

            $user = \App\User::where('email','[email protected]')->first();
            $user->notifications()->create([
                'type'=>'success',
                'heading'=>'Success!',
                'content'=>'E-mail update has been successfully sent to the group of users!',
                'action_link'=>'javascript:void(0)'
            ]);

        } catch (\Exception $e){
            report($e);

            $user = \App\User::where('email','[email protected]')->first();
            Auth::user()->notifications()->create([
                'type'=>'error',
                'heading'=>'Error!',
                'content'=>"Error sending e-mail updates to users! Please check log file for more information.",
                'action_link'=>'javascript:void(0)'
            ]);
        }
    }
}

** App\Mail\EmailUpdate.php **
<?php

namespace App\Mail;

use App\User;
use Illuminate\Bus\Queueable;
use Illuminate\Mail\Mailable;
use Illuminate\Queue\SerializesModels;
use Illuminate\Contracts\Queue\ShouldQueue;

class EmailUpdate extends Mailable
{
    use Queueable, SerializesModels;

    public $user;
    public $subject;
    public $update;

    /**
     * Create a new message instance.
     *
     * @return void
     */
    public function __construct(User $user,$subject,$update)
    {
        $this->user = $user;
        $this->subject = $subject;
        $this->update = $update;
    }

    /**
     * Build the message.
     *
     * @return $this
     */
    public function build()
    {
        return $this->view('emails.emailUpdate')
                    ->subject($this->subject);
    }
}