TypeError: Argument 1 passed to App\Models\Categories::findById() must be of the type int, null given, called in /data02/virt67210/domeenid/www.retrosonic.shop/htdocs/views/product.php on line 10 in file /data02/virt67210/domeenid/www.retrosonic.shop/htdocs/retrosonic-future/app/Models/Categories.php on line 79 #0 /data02/virt67210/domeenid/www.retrosonic.shop/htdocs/views/product.php(10): App\Models\Categories::findById(NULL) #1 /data02/virt67210/domeenid/www.retrosonic.shop/htdocs/index.php(30): include('/data02/virt672...') #2 {main}