Cancellation nightmare

I am leaving the country at the end of this month. I have been trying to cancel my LTE service since 13 Feb without any luck. I have emailed the cancellation form to ********** on 13 Feb. I have followed-up with calls and emails several times, I went to a Telkom shop who once again escalated my case. My case has been escalated so many times it must have reached the CEO by now,but still no luck. I have complained on their Facebook but that did not help much. I really don't know what else to do, all they ever say is that they will escalate my case! The only option left to me is to get legal help.