DSTV is ********** and *****ing my money

I always pay my DSTV acc at PNP tillpoint.On the 1st Sept i paid my account as usual at the tillpoint.On the 2nd a debit order for the full amount went of my bank.I logged a call to find out who gave dstv permission to debit my bank acc. And what will happen with the extra payment.It is now a week that ive been trying to get my money back or answers. Pathetic service when you phone them.Then they even give you false info as to who i must phone at billing dept.