Waiting for feedback for 2 months on wrongful upgrade

In December I wrote about the extreme bad customer service given by MTN where my contract was upgraded without my permission and MTN promised to come back to me as they were still investigating. Its been 2 months now and still no reply. The thing is they had guts to debit my account, 2 months after my contract ws terminated. Let a lone the debit orders of R900 for 6 months for an upgrade I did not authorize.

I just wonder what will it take for my concern to be addressed.

Regards Still disappointed