Billing issue

I have been struggling with MTN with getting resolution with my contract billing. I am sitting with a bill that no one at MTN is unable to assist me with. I was told that I called in the call center 78 times to purchase data amount to R110.10 were as my account is locked at R470 and I cannot purchase data from the contact center or the app that is more than R470. when I ask to how this happened they cant explain. Someone is committing ***** on my account but MTN is sending me from Pillar to post. I am going to contact the Ombudsman maybe they will help me about this because MTN consultants are useless.