Double charging on account

I had a drifter but in April 2014 I bought a walker and phoned multichoice to deactivate the drifter and activate the walker. I found out in December 2015 that they did not deactivate the drifter. And I have been paying R49 for it since April 2014. I phoned in December 2015 to sort the problem out. They would have gotten back to me. They also have taken a double payment for the explora in November 2015, which I also queried but got no feedback. I have mails that I requested where the query is in process. I have also send them a bank statement showing they charged more for the explore in November 2015. But all I ever hear is that is it still with finance. It has been 3 months now. How long does it take???? Yesterday I got a mail from multichoice stating the cancelled my mobile devices per my request. But when I spoke to them this morning they say both devices is still active.