Bad service

I book in a TV on the 27th of April for repairs does not switch on. After almost 2 months I was told to come and collect the TV because it s fix. After testing it at the store the same problem still not switching on so they must book it in again. What about your promise that after 21 days if it not fixed you will refund or replace. I drove 80km for nothing and again will be without a TV for another 2 month. Ref no 11277