Mtn contract cancelation delay

Hi.. Hello Peter I'm currently having a bad experience with mtn, I was having a contract of Home package data on a special rate of R265 a month with Mtn which has expired last year October and on the 21 of November I requested a cancelation they said the cancelation is completed and on December I will still be billed for it for the last time because it must serve a period of 30days of which they did took their money, but to my surprise they also billed me for January this year I called their contract department regarding the cancelation they told me that the person who was assisting me on the 21 of November did not complete the process and they said it's canceled but to my surprise it is still not cancelled and they again billed me for this month I'm requesting a refund and a cancelation