MTN lack of being a 'SERVICE PROVIDER'

MTN Very eager to deduct money from a debit order but when it comes to customer service and credit notes that HAS to be made or credited back into my account you will have to wait 3 months if not more.

I did an upgrade on 8 May 2019, the upgrade was successful but it did not replace my existing contract... In fact they decided to charge me standard tariffs on 10GB DATA per month of R499.00 (it was a PROMO 10GB on previous contract of the value of R299.00 for 20GB day and 20GB night data)

So basically they deducted these amounts for 2 months towards my BILL and now they do not want to refund me.