Pathetic Cell C

I feel hopeless as I read the horrific reviews of Cell C just done for today and I can only imagine this will just be another water of a ducks back by adding mine. I recently cancelled my business account for June '19 and received confirmation of cancellation and all was good. 2 Days later I receive my statement with additional charges and once I queried it, the call center confirms that it must be an error they will log a call and it will be credited. Today I try to follow up and what a surprise "due to the contract I have, I now have to pay for the extra charges because my contract was due for renewal" how does this even make sense????