Account closed but apparently I still owe money?

Dear Cell C<br> <br> I had a two year contract which terminated in early December. This was cancelled in accordance with your business rules. I've been on direct debit since inception of the contract and have experienced no problems to date.<br> <br> Now my family are receiving calls (I'm out of the country at present) saying I still owe money. Why? And surely this should have been debited from my account if it pertains to calls made in the final month of the contract?<br> <br> i'm happy to settle any monies owing but require further information.<br> <br> Please get in touch via e-mail as I'm currently abroad.<br> <br> Thank you.<br> <br> Regards<br> Justin