poor service from MTN

There has been a mess up on my contract which I recently upgraded. I have been trying to resolve the issue with MTN however, it has been almost impossible to get in touch with a competent consultant who could assist. I have called the call centre and I have been transferred from department to department. I received a call from Mondo MTN on Saturday with the undertaking that I would receive a call/email the same afternoon with a way forward or resolution of the matter however do date I have not received any correspondence. Emails to MTN customer care also proves futile. I am really frustrated at this point and do not know who to contact to get this resolved.