MTN loyalty retail vouchers don't work.

I have purchased Vouchers last year at Total Sports, with my MTN loyalty points, the day I bought the voucher tried to use it at the store it, the system displayed the voucher is used. According to MTN app the voucher was not used. tried 2 more times same result. contact MTN no resolve or reversal of my points. Bought a voucher for Incredible connection in January tried at a few stores they say the vouchers don't work sorry. So thousand of points later I basically bought none valid store vouchers.