Incorrect billing

My services are suspended because I have an outstanding balance to pay. On 14/10/2023 I spent almost an hour with 3 consultants and they all couldn't tell me why I have an outstanding balance. Invoice I*** was for R1049 and due 31/10/2023.

On 31/10/2023 my bank account was debited R1049

On 08/11/2023 my bank account received a refund “IMMEDIATE TRF CR STD SA. MTN REFUNDS 18BO704153”

On 14/11/2023 I receive a sms stating that I have outstanding balance of R339. And i made the call and sent email no help.

On 15/10/2023 i wake up to an sms stating "We have had to suspend your ability to make outgoing calls due to non-payment on your MTN account."

How do you deduct money, refund a person and come back and say they are owing? I am puzzled