Poor customer experience

I went to foschini clearwater mall on the 20th of Sep to take my phone in for repairs as the charging port has stopped working , I informed them that i had lost the slip but i bought the phone using my account , i gave them all the details date of purchase , account no etc . I was told i will get a call once they get the slip . After a week i got a call from them to say they still searching for the slip . Its almost a month now and theres still no feedback . the number *** just rings and no one answers . My warranty is about to lapse now . I also spoke to Thabiso at the store who promised to follow up but he never called me back . What do i need to do to get assistance as the call centre refers me back to the store that never answers their phone .