Refused refund for data

I recently purchased R1999 for 200 GB on a data cell number of one of my contracts which expired just over a year ago. It turns out someone else had received the number and submitted it to RICA. We were then told if we can provide the paper work and SIM card supporting the cell number is ours and they might be able to to a SIM swap for R10. We returned with the paperwork and SIM card proving that we were the rightful owners of this number. The new owner of the the cell number was contacted and refused to cooperate. He got 200 GB of data at our expense! We then asked for refund and Cell C refused. No where on the contract did it state my number will be given to someone else after a year!