Terrible Service. MTN don't care about their loyal customers

I have tried numerous channels to contact MTN and have this resolved but all are completely unhelpful. This includes going into their store, using Twitter and calling the call centre. I app**** for a contract and it was declined and I was requested to call Transunion. I was surprised as I have no poor credit issues. I called Transunion and obtained a copy of my credit score which shows no negative issues on any aspects. I currently have 3 MTN contracts and have never missed a payment with them or any other service provider and this shows on my Transunion and other Credit scorers report. I have been trying to contact MTN credit vetting department to resolve this issue but nobody is even able to tell me how to get a hold of them. On Twitter they promised to get a manager to call me but this never happened and now they don't respond. The call centre is unable to assist and neither is the store. Really poor, pathetic service for someone who has been a loyal contract customer for over 12 years. I hope someone would contact me to resolve this asap.