I am trying to code a database notification using Filament in Laravel but it seems it won’t send out notification to users who was assigned to service order. Is it possible to do this way

ServiceorderOberserver.php Observer

<?php

namespace AppObservers;

use AppModelsUser;
use AppModelsServiceOrder;
use FilamentNotificationsNotification;

class ServiceOrderOberserver
{
    /**
     * Handle the ServiceOrder "created" event.
     */
    public function created(ServiceOrder $serviceOrder): void
    {
        // Fetch the users who are assigned to this specific service order
        $assignedStaff = User::whereHas('serviceOrders', function($query) use ($serviceOrder) {
            $query->where('service_order_id', $serviceOrder->id);
        })->get();

        // Loop through each assigned staff member and send the notification
        foreach ($assignedStaff as $staff) {
            Notification::make()
                ->title('New Service Order: ' . $serviceOrder->pOrder)
                ->body('You have been assigned to service order ' . $serviceOrder->pOrder)
                ->success() // Styling for the notification (optional)
                ->sendToDatabase($staff); // Send notification to each staff member
        }
    }

    /**
     * Handle the ServiceOrder "updated" event.
     */
    public function updated(ServiceOrder $serviceOrder): void
    {
        //
    }

    /**
     * Handle the ServiceOrder "deleted" event.
     */
    public function deleted(ServiceOrder $serviceOrder): void
    {
        //
    }

    /**
     * Handle the ServiceOrder "restored" event.
     */
    public function restored(ServiceOrder $serviceOrder): void
    {
        //
    }

    /**
     * Handle the ServiceOrder "force deleted" event.
     */
    public function forceDeleted(ServiceOrder $serviceOrder): void
    {
        //
    }
}

I have tried reading the documentation but I can’t find any solution to my problems. I wanna add more details about my code. The Service Orders can assigned many staff so I have create a pivot table for that. My Service Order model looks like this

ServiceOrder.php model

<?php

namespace AppModels;

use IlluminateDatabaseEloquentFactoriesHasFactory;
use IlluminateDatabaseEloquentModel;

class ServiceOrder extends Model
{
use HasFactory;

// Fillable fields for mass assignment
protected $fillable = [
    'pOrder',
    'clientAddress',
    'clientPhone',
    'description',
    'registeredDate',
    'assignedDate',
    'handoverDate',
    'estimatedTime',
    'status',
    'remarks',
];

/**
 * Define many-to-many relationship between ServiceOrder and User.
 * A service order can have multiple staff members assigned.
 */
public function assignedStaff()
{
    return $this->belongsToMany(User::class, 'service_order_staff', 'service_order_id', 'user_id')
                ->withTimestamps(); // Keeps track of when the staff was assigned
}

/**
 * This relationship returns the users associated with the service order via the pivot table.
 */
public function users()
{
    return $this->belongsToMany(User::class, 'service_order_staff', 'service_order_id', 'user_id');
}

}

And my pivot table looks like this

public function up(): void
{
    Schema::create('service_order_staff', function (Blueprint $table) {
        $table->id();
        $table->foreignId('service_order_id')->constrained()->onDelete('cascade');
        $table->foreignId('user_id')->constrained()->onDelete('cascade');
        $table->timestamps();
    });
}