Upgrade disaster

I upgraded on 17 December 2020 and was told that I would get a R1200 grocery voucher with the upgrade, as well as 20 gig data that will not expire. To date I have not received any of the above, and when I phone them, I'm just transfered to an external company. I did not upgrade with any external company. So I feel it's not my responsibility to sort it it out with them. I upgraded with Vodacom, so I want them to reimburse me and fulfill their promises.