Unsolicited Spam with no way to opt-out.

I am regretting Porting to MTN. I would have left them already if I had not had to wait 3 months before I can port again. After porting to MTN via Afrihost, I was bombarded with Marketing SMS's from MTN. Afrihost emailed me a few numbers to dial, to be able to unregister from the SMS's The situation is now I receive and Double your Data SMS every day at just after 1 PM. I tried to un register via Stop or Opt-out and I get a message back from "Facts" saying they are invalid Codes. I called MTN call centre and have been pushed from pillar to post trying to stop these unsolicited sms's. I was first told to call certain codes to cancel, yet some registered me back onto spam which I had to remove again. Then I was given 2 numbers, one for Marketing and retention and the other for technical. Both number where wrong, one just sent me back to "135" Next a ticket was sent to the technical department and I was told to wait 24 to 48 hour, which I did, yet I am still getting the sms's. I called just a moment ago only to be told that the last operator had escalated the issue and still there was no response from The technical department. I have now wasted a week trying to get what should be a simple problem resolve, It makes me worry that a simple solution can't be handled by such a big corporation. If this issue is not resolved here, I will be going to WASPA and complaining about the unsolicited sms's.