Wrong billing I want it fixed urgently

I am billed 1000 rand for dstv compact plus and I called the call centre which confirmed that they are not sure why as well , but promised they escalated the case , up until no one from dstv has called me and my payment date us tommorow , and I am afraid they might switch the decoder as I am a cash paying customer.I need someone from multichoice to urgently solve this .