Iphone 12 pro earpiece not working

Hello, i have a problem in my iphone 12 pro ear piece which has stopped working, cannot hear a phone call expect from loud. I have also read on apple that some of the phones have problem and it could be repaired free of cost.

i am from Pakistan and travelling to uae tomorrow, can i just pop into any apple store in UAA for fix or do i need to book an appointment

seeking support

Thank you