******* and poor, disgusting service

In May 2013 an MTN telesales agent contacted me offering a cellphone contract for 24 months.We agreed on the contract and the phone was delivered to me.MTN was supposed to debit a fixed amount of R114.00 a month for 24 months since the contract was a top up.However few months into the contract the monthly amount kept on increasing and I send an email enquiring about that but to no avail.Furthermore in March 2015,I contacted the call centre inquiring about cancellation of the contract procedure and I was informed that I have to submit a cancellation letter which I did on the 20th April 2015.MTN did not do anything about the letter until their staff went on strike on the 20th May 2015 and they only send to me so called cancellation forms on the 13th June 2015.I took those forms to the shop at the East Rand Mall wherein I was assisted by one lady by the name of Thembi who was uninterested never mind listening to my problem.I completed those forms and left them with her as she told me she will forward them to the relevant department.MTN has since send monthly airtime and data bundles despite the fact that the contract has ended and I am worried that they will again bill me for that.