Cell C shoddy service

On 17 July my husband went to cancel his Cell C wifi contract early , at the Midlands mal lin PMB. He was told to pay R300 at PNP, to pay up the router and give cell c the POP. He was given no proof of cancellation as he was told they do not make photocopies but was assured it would be cancelled. He called in the next month to ask if the amount deducted was for cancellation costs as it was not the usual R640 but an amount of R500. He was assured that this would be the last charge. This contract was never cancelled and we have been going back and forth fighting the cost that has now risen to over R2000! We have not used the router (it burnt out in July) nor any of the data and they can see this. We have been told that we must pay this amount to cancel now or they will keep billing us even if its an unused service. I have been through to their headoffice and they have escalated it. My husband was called yesterday and told again by someone senior to pay the money or this contract will NOT be cancelled. Due to the Midlands mall staff in pmb not doing their job we are now stuck with an account for an unused service which we cannot afford nor think is fair for us to pay. This is going to ruin our credit rating and is very very unfair and stressfull and all because of someone giving incorrect info and not doing their job and following up properly that the acc .was cancelled. My husband believed what he was told and now he is sitting with the consequinces. I do not recommend Cell C to anyone and will be cancelling my own contract with them in due course. Ill just be wiser and make sure I get evidence of MY cancellation, as you cannot trust them to do their jobs.