Refund refusal

I bought a tv a while back, it got damaged it was still under warranty, i sent the tv back to the shop. it was sent to the manufacturer who later declared the tv not repairable and advised that the shop will have to refund me. At the shop they initially agreed to refund me within 19 working days, that did not happen, almost 2 months later i am told they will not refund me and i am not getting the tv back, because their head office declined the refund, and the store manager refused to give that in writing.