INCOMPETENCE FROM MTN

I once had a contract with MTN, I closed it and paid it off, after 5 months of cancellation, they tried debiting again, I called only to find out my contract was active again with no clear explanation or reason, they gave me a case number and promised to fix that but instead I was referred to attorneys and the amount keeps on increasing, whenever I try to find out why they tell me that I should just settle the amount with no proper explanation 😒