MTN Phone Upgrade disaster

I was due for an upgrade, received an email stating courier would contact me. Turns our incorrect courier stated on email by MTN. (1st issue) Met courier, unfortunately biometric fail (thumb prints) - Have been trying for just under 2 weeks now to get the upgrade device delivered, or collect it !! Called MTN virtually daily, and promised "Manual release done" yet absolutely nothing gets done. I am paying MTN, yet dont have the upgraded phone !! 2 weeks of trying, 2 weeks of calling MTN daily, but NOTHING is done. Tried to request manager, again promised call back, NOTHING. Not sure what to do !! On the verge of cancelling contracts. Help