Never got my Huawei voucher

I bought my Huawei nova 12i at Mtn store in kenako mall, gqebera last year in August. So it came out with free earpods, R300 pick n pay voucher and R600 voucher to buy at Huawei online store. So the problem is that I couldn't activate the vouchers so I asked the Huawei sales girl to activate for me, she told me that she forwarded my details to her manager to activate for me, after a day or 2 she sent me a link so I got my vouchers. The only problem is that when tried using the Huawei voucher in their online store it said the voucher had already been used. So I never got that voucher which I was gonna use to buy a Huawei smart watch.