POOR SERVICE FROM MTN

I did a promotion deal/contract over the telephone with Sipho Ntuli at the Johannesburg MTN region for a data router with 20 gig day time and 20 gig night time during November 2018, even though the contract said 5/5. In Jan 2018 I ran out of data and when I queried it Sipho confirmed that my account was activated for 20/20. Since I used wifi at the office I never ran out if data again up untill last Wednesday, 4 July. I contacted MTN just to be told I am still on 10/10. I eventually was able to talk to Sipho again on Thursday and he then sent an email to the relevant department to clarify the matter. He contacted me this morning, Monday, 9 July, to confirm that the problem has been resolved and that I am on 20/20. Well, when I wanted to connect I was still out of data and when I phoned in to the call centre I was once again told that I am on 10/10. I sent Sipho a sms, he said that he sent the relevant department another email to investigate ... even after he told me this morning that the problem was resolved. I am frustrated with the service that I have received from MTN. I have been a client of MTN since 1999. The number for the data router in question is ********** 212.