Poor service of KFC online app

I ordered on KFC app then i put banking details for the order then the kfc didn't give me an order no of which it deducted on my account.

Then i called KFC customer care of which was told they will investigate after a week they came back and say they will give me a voucher i was fine about it. I tried to put a voucher again using online order since was loadshedding the network internet was not good cause it was keep went offline after i put the voucher of which it ended up saying is invalid.

Then i call again customer care then was told to email the problem with voucher no of which i never get a response its a month i want my money cause the voucher was given didn't work