Services not cancelled

I had Cellphone Insurance and a Subscription for the Magazine which I cancelled qiute a while ago. Then I settled my account to R0.00. The out of the blue we received a statement which stated that we need to pay one month's Subscrition Fee as well as a fee for the Cellphone Insurance. So I thought it was maybe a mistake on their side because I know we cancelled that so we can't pay for something that was cancelled a while ago and we also didn't receive the Magazine anymore. Then a consultant phoned my husband to ask for payment and my husband explained to the manager that all this was cancelled before so the manager told him he was sorry and would sort it out. He also took my husband's email address to let him know that everything was sorted. Now my husband receives messages that if we don't pay that outstanding amount legal action will be taken. We never had any problems with TFG until now. I think its totally unacceptable for us to be held accountable for something we don't even use and already cancelled previously. We are going to close the account because we don't want this bad service in the future.