Poor Service and *****

Worst service ever from MONDO and MTN, First MONDO sold me two sim card contracts while I only agreed to one, I didn't know about this until my bill was high for the unpaid sim card. I complained, they launched an investigation and MONDO told me they will pay for the other sim card, this is from last year JULY 2021, till to this day I have issues, and with MTN knowing the issue they still went ahead and put my name/account as default from credit bureaus and now I can not do anything due to a problem that was caused by MONDO and MTN. Worst part is, I constantly do follow ups and no one is responding to this. If I ever knew this, I would not agreed to their data contract, this is by far, the worst service I have ever received from any provider. This is sad because my credit score is ruined and I have to pay for a service I have never used. If it was possible, I'd open a case against them.