Paying for an old black friday deal which I am not getting.

I upgraded my number, *** on 15 March 2023. I had a black friday package which I paid R199 per month extra on my previous contract. I am still paying this amount but do not get black friday data for it. It's been since the end of March and it is now 5 months that I am paying R199 per month extra for something I do not get. How can this be fixed and reimbursed? I did not get any data so I need to get my money reimbursed ASAP. It's adding up now to R995. I phoned numerous times to get this sorted and either I get no feedback or it escalates each time with no solution to the problem or while I am speaking the phone call drops and I have to start all over and speak to someone new and explain all over again and then the phone call drops again. Each time no one is phoning me back.I even went to the shop where I upgraded and they said they can not assist me and I need to phone 135....... One month later after my email to MTN it is still not resolved and no communication from MTN. Another invoice later and still paying the R199 for nothing. it is 6 months now.