Bad services received from MTN

I have launched a complain about unreasonable debit orders that were going through every month for 4 months until I went to bank to stop it. They promised to resolve or look into my case but since then they never help me. Now they blocked my number even handed over my account for collection without me getting to know what caused my account to go up like that. Today went to MTN to revisit my contract then the shop realized that there's a number that is been used under my contract that caused this whole thing. I am very disappointed with MTN an thier level of service because now the store can't help me because my account is closed from.thier side and handed over. I want my number back and my name be cleared while they busy checking how did that number charge on my account.