Laravel 10 event handle runes two times.

$reference = "ABCD1234";
event(new AppEventsRewardOnBooking($reference));

when i fire this event then every thing is fine but it’s handle function fires 2 times.
this is how i register this in EventServiceProvider class

protected $listen = [
    // ...........
    // .............. 
    'AppEventsRewardOnBooking' => [
        'AppListenersAddCredit',
    ],
];

In the RewardOnBooking class I’m just doing this nothing else not even broadcastOn() somthing –

public function __construct($reference)
{
    $this->reference = $reference;
}

and in the AddCredit class nothing to construct, i’m just handle

public function handle(RewardOnBooking $event): void
{
    $userCredit = Credits::where('user_id', '=', Auth::user()->id)->orderBy('id', 'desc')->first();
    if ($userCredit == null) {
        Credits::firstOrCreate(
            ['user_id' => Auth::user()->id],
            [
                'creditsAmounts' => 0,
                "description" => 'added credit for your first booking',
            ]
        )->first();
    } else {
        $amount = rand(1, 5);
        Credits::create([
            'user_id' => Auth::user()->id,
            "creditsAmounts" => $userCredit['creditsAmounts'] + $amount,
            "description" => 'Added credit for your booking reference - ' . $event->reference,
            'responce' => $amount,
        ]);
    }
}

I am trying to do when this event is happened then add some random credit amount in user Credits but this i is happened two times

This is what stored in DB

but i just want to do this ones.

You can see this DB recodes