Failed cancellation of contract that lapsed in 2015 already

<p>Cancellation was done in person at Matlosana Mall with Logan Pennels. Cancellation letter was sent to her on my company letterhead and she sent it to Mtn. Subsequently, the corresponence was sent to mtn several times. The contract was only cancelled in January 2017. I have paid for services that I have not used it all since Aug 2015. Mtn refuses to refund me fir that time, because they have apparently not received the cancellation letter any of the other times, even though I have sent them all of the proof about 50 times. I have two other contacts with mnt that I am going to cancel as well. I do not want to pay them one more cent. They are beyond useless.</p>