Keep getting told someone will contact me to resolve issue but no one does.

I Bought A new DSTV decoder with full installation. When the installer came out to do the installation they said there is no voucher do for the installation. I then called Ebucks and the lady said she will get back to me, one week later still nothing so I call again and speak to Mlu, he did get back to me and said it is with the relevant department and they will contact me. Now 3 days later and still no one has got back to me. This morning I called again, same answer, someone will call me back with feedback... still nothing. Please can someone help with this, or I would like my money back and I will get it from somewhere else!