Ineffective refund system

I did a refund at PNA horizon view on the 18th of March 2024.To date I have not received my money.I did a follow-up by email at the store however,was told to forward the receipt which I did.Then no feedback afterwards.During the process of refund I was only told about 3-5 days and subsequently on email they advised 10-15 days.Im not happy at all with their service.Why should it take this long to refund a customer? If their refund system is not effective,why still apply it?