unfairly treated

on the 2nd September I settled my contract at the Glen Mall Vodacom shop, they sent the proof of payment and copy of ID to cancellation department. A week ago I phoned in to confirmed it was settled and closed they said yes and will receive confirmation letter with 14 days. I recharged airtime and noticed it was not getting finished when I checked my balance they have given the minutes, data and SMS. When I called in they said they did not receive the document , on the 9th I went back to Vodacom shop to resent the documents and the lady who assisted mw confirmed that they were sent but send anyway and ccd me on the email. Now Vodacom send me SMS to say I must pay for that I used but when I phoned I asked to remove the everything they said it will be removed but wasn't removed. Now I'm expected to pay for something I never agreed upon, I need them to close the contract and send confirmation of closer