refuse to exchange Tablet with factory fault.

I bought a tablet at Pep store in Upington on 17 Oct 2015. On arrival at home I realised that the tablet had a faulty battery because it was fully charged and the following morning it was off and the battery was flat. I monitored it for 3days and realised that there was no change.<br> I took the tablet back to pep at greenstone mall in johanesburg and a lady called Doreen said she called the upington's store but they need proof. The lady said she cannot refund me or exchange the tab since I bought it at the other store, she even suggested I take the tab to vodaworld of which I told her she was being unfair because I bought the tab at pep store not the mmanufacturer. <br> My problem is that they are trying to drag the isue until 7days guarantee lapses to avoid exchangin or refunding me.