topnotch_website/app/Services/PaymentService.php

<?php

namespace App\Services;

use App\Models\Payment;

class PaymentService
{
    public function distributePayments()
    {
        $payments = Payment::where('unapplied_amount', '>', 0)->get();

        foreach ($payments as $payment) {
            $payment->applyToInvoices();
        }
    }
}