Account blacklisted

Yet again I have the pleasure of dealing with Cell C.<br> I have settled my account and yet they do not check their records but notify me that I have instead been blacklisted.<br> Take into account that no letter of demand was ever sent in terms of the NCA. When have cell c ever cared about customer service though?<br> I have sent two queries to customer care and someone has yet to contact me.Phone the call centre and you just don't get through so you can't even speak to anyone.<br> Dear Cell C I strongly advise you to clear that listing -if not I shall be taking legal action for defamation and costs shall be for your account.