Demanding credit

Wow after I've written to vodacom disputing the increased migration on my contracts they finally reversed it back to original plan but to my surprise the credit hasn't been reversed then 2 days ago I got an sms with the bill of the same amount I disputed,mind you the error is on their side to start with.my worry is that the debit date is fast approaching which is the 20th and I don't know what to do I this case because with this migrate I'm expected to pay extra R700 which I don't have and never will.

My question is what will happen to the agent who caused all this because of dishonesty?I don't think I will take any contract with vodacom in the future.can vodacom sort this out since they decided to ghost m