Brocken plasma with guarantee

Hello Peter I buy a Plasma at Ok Funiture I buy it cash by them I have it for a year and month than the volume did want to play I sent it back and I got it was right for 3 weeks it was playing than it just go off I sent it back when I go to them they demand by me a R150 to open it when I tell them I won't they say they don't have a spare to fix my plasma than again they say my plasma is ****roache damage and is not insured so I'm helpless than the women by ok Funiture say I must go nd do what I want to plz can Yu help me bec I save a year nd half for that money I won't get it back