MTN Keeps on passing the buck!

I have been a long standing MTN customer and have 2 cell phones on 1 contract. Last year in November one of my phone's got ****** which was replaced by MTN insurance Pinnacle Marketing. Everything has been going well until the 05 June 2018 when my phone showed Emergency Calls only. I backed up my phone, updated my OS and did a factory reset but this did not resolve my issue. I swapped out the sim card works in a second phone so it's not the sim card. I went into MTN Cresta they sent me to Hauwei shop in Melrose Arch. They checked and gave me a print out showing that my phone has been blacklisted/greylisted with a ITC Ref no: ********** 8. Next stop was MTN Cresta again and was told they did not blacklist me and it was a replacement phone not supp**** by them so they could not assist me. So I contacted Pinnacle Marketing (MTN insurance brokers spent an hour on the phone with them to try an see how to assist me I was told that the replacement phone came from J Cell Bar, Pinnacle suggested I go back to MTN as they could not black list me. So back to MTN they were insistent that this is not their problem. Which is ridiculous my contract is with them!!! I called Vodacom to see it is blacklisted on their network it is not. I have exhausted every avenue and MTN been back and forth and they just keep on passing the buck...they are happy to take my money and I'm stuck with a phone on contract that does not work!! Considering changing service providers.