MBD erroneously charging me interest and fees for account transferred over

My Vodacom account was handed over to MBD after I not being informed of it being handed over. I raised this issue with Vodacom as well. I had made payment arrangements with Vodacom to settle a final amount on account which was pre-cancelled in 2017, the only the reason Vodacom still had an amount to be settled was because of a usage amount which they did not include in their settlement balance to cancel my contract in 2017.

I was also not informed of any fees to be charged by MBD in terms of legal fees or any interest, in fact it's the first I am hearing of such a thing happening with an account being handed over. I spoke to a consultant a few days ago and confirmed I have one final amount of R664.37 to settle what was owing to Vodacom and then I would have settled in full. To my surprise and shock I am told legal fees and interest fees are being accrued, despite confirming the final amount will be settled end of October based on my original agreement with Vodacom on the payment plan.

I will not accept paying additional fees or interest where I was caused unnecessary inconvenience in getting this matter settled in an amicable matter with Vodacom and instead being told it's handed over without written notice or an attempt to inform me of it.