Ok store mabopane

I bought a tv at OK furniture at mabopane back in 2016,this year july the tv just went blank while i was watching it but sound was coming out, i took the tv to the store and we found that it's still under warranty, hisense was apparently contacted same july to come fix the tv, i waited for weeks until i went to the store enquire only to find out the tv is still at the store, i took further steps to contact the technician and hisense head office and only then was the tv attended to, they tried to fix it and found that it cannot be fixed and last week i was told by hisense complaints manager to apply for credit, he gave me a reference number to give to the store... Now the store has everything they must give me a new tv I'm being sent around, they want proof of purchase which they have on their system because i bought the tv on account, now they're telling me to go make an affidavit that i lost the proof of purchase of the tv, how are the police gonna issue an affidavit for something they're not sure off? How do they know i bought a tv? Ok mabopane store has poor disgusting service, i wouldn't advise any1 to buy anything at that store.