Mwe
Contract in "terminated status" but still pay

I am a Mweb customer for the past at least 3 years. The contract I purchased last year at the Centurion store is the R139.00 data contract for 2 gig. My last two accounts was bigger amounts. According to the support staff I have to monitor my own usage, BUT during our discussion they determined that my account is in "terminated" status with the service provider Mtn and am now investigating this for the past 2 weeks.
Why am I paying for service which I can not use currently?