Installation for dstv

We bought a dstv decoder about 2 weeks ago (13 September 2017) that included a free installation voucher. However non of the dstv installers want to install with the voucher we received but they want a cash payment of R450, reason being that Multichoice takes forever to pay them with the voucher some say they don't pay at all. We've contacted about 5 people 2 were contacts we received from multichoice but we still got the same story. We've tried communicating with dstv on their Facebook page since the 15th of September they keep saying they have escalated the query but we still don't have any feedback or update from them to this day. They only respond when we enquire about the progress. This is so frustrating why does multichoice offer free vouchers when none of their installers want to do it for free?