Billing extra money on my contract

The west ever service provider when it comes to billing. You go to the branch you won’t get assistance rather to be referred to call centre even there you won’t be assistant.

I renew my contract in May this year with new banking details and new debit date. They are still using both accounts and obviously they won’t get the money on my old account, they have been charging me rejected fee of more than R200 and on the other side the bank is also charging me R100.

So in simple words for the past 3 months I have been paying R 300 extra on my contract and Telkom is doing nothing. Because every month they are benefiting R200 extra so they are making profit out of me.

I really don’t what to do anymore