Data not loaded after calling Mtn several times over a month

Went to cancel my contract before December 2017. Had problems with Mtn several times that i decided enough is enough. When my data was not loaded and i called them, their system shows no data loaded. After a few days called again and by the 3rd time i am told it was loaded before i called the first time. On the day i went to cancel, i, idiot that i was, took an upgrade with 10gig of data. No 10gig data since December 2017 and over 6 times calling. They do not consider this as breach of contract. Bad service if you start having problems with them.