__clone method called on non-object /line 59 Laravel 8

<?php

namespace AppConsoleCommands;
use IlluminateConsoleCommand;
use AppModelsUser;
use AppModelsevent;
use AppModelsEnrollment;
use AppMailSendMail;
use IlluminateSupportFacadesMail;
use IlluminateSupportFacadesDB;
use CarbonCarbon;
use IlluminateSupportFacadesNotification;
use IlluminateNotificationsNotifiable;

class SendNotification extends Command
{
    /**
     * The name and signature of the console command.
     *
     * @var string
     */
    protected $signature = 'send:notification';

    /**
     * The console command description.
     *
     * @var string
     */
    protected $description = 'send automatic notification to users that enrolled in events a day before the event date';

    /**
     * Create a new command instance.
     *
     * @return void
     */
    public function __construct()
    {
        parent::__construct();
    }

    /**
     * Execute the console command.
     *
     * @return int
     */
    public function handle()
    {
    
       $events = DB::select('SELECT events.start_date , enrollments.user_id , users.id, users.first_name, users.last_name, users.sex, users.users_phone, users.password, users.email  FROM events , enrollments , users where events.id= event_id and enrollments.user_id=users.id');
        

                foreach($events as $event) {

                $created = new Carbon($event->start_date);
                 $now = Carbon::now();
                 if((($created->diffInHours($now))>=24 )&& (($created->diffInHours($now))<=48) && ($event->user_id == $event->id)){
                
                app(User::class)->fill(['id' =>$event->id,  'first_name' => $event->first_name, 'last_name' => $event->last_name, 'sex' => $event->sex, 'users_phone' => $event->users_phone, 'email' => $event->email,'password' => $event->password])->notify("Your deadline is in  day!"); 
                 }
            }        
        
    }
}