Telkom month to month sim contract

I have a problem with Telkom , since I cancelled my month to month contract last year November. By the time I cancel my contract I made a mistake and disputed last payment,so Telkom called me and went to the store and they explained to me and I made a payment with reference I was given at store . My problem at this moment Telkom is debiting me while the SIM card is no longer working. Today they even sent me an sms of notice of Judgment. Please help me