UNISA 3G CELL C DATA BUNDLE ACTIVATION PROBLEM

We paid UNISA R600 for a 3G Data bundle through Cell C. Received a receipt from UNISA for the payment on 6th January 2015, followed correct procedure as per T's & C's. However, to date we still do not have activation!! Numerous emails and still no response. Telephonic contact is totally impossible, they NEVER answer! Cell C claim UNISA has not paid them and therefore no activation. We either get what we paid for or our money back!!