Coupon redemption

I have received 2 emails saying I have awarded a voucher for my 1st instalment. I could last week and spoke to Justin and I lost on the 200 voucher and yesterday 16/01/2023 I received an email about the R100 voucher. Again I called but it seems as the sales department don’t know how to activate the voucher, I have been on hold for an hour with no assistance. My issue is these voucher have got a time frame and the sales department don’t know what they are doing… May I please get an assistance as my second voucher expires 18/02/203 @ 20:00