refuse to swop a faulty decoder

My Dads decoder has been giving problems. He took it to his local DSTV outlet and they asked him if he had insurance. he said that he had and the lady checked and stated that she did not have stock but if he took it to Randburg they would be able to give him the decoder immediately. He was told at Randburg that due to it being a technical fault that they cannot replace the decoder but if it was due to lightening or theft they would replace it. He was also told that the insurance runs in a 3 monthly cycle and therefore he must either wait 3 months or pay R 700 and the decoder will be replaced. He cannot afford R700 as he is a pensioner and my niece pays his DSTV so that he can have some form of entertainment. My dad at this moment cannot watch TV as he is now waiting out the 3 month period which I think is a load of nonsense. I have had DSTV from the beginning pay the insurance and when I have a technical fault I take it back and it is replaced.. I sent a complaint in and it took 3 days before someone came back to me station that I must send an email to [Email Removed] - well that email does not exist...