MTN Retentions - contract cancellation

I am so disappointed with MTN retentions,I've been trying to cancel my contract now for 2 months with no joy.I upgraded and the device was never delivered to me,when I called after 2 weeks to cancel the contract I was been told one thing and the other.Apparently they had to wait for their warehouse to send them RMA to prove that the device is still with them,this has been going on for over 2 months.The supervisors keeps promising to contact me and nothing.The names of the supervisors are Tiny and Sherika,meanwhile 2 debits have been gone off my account for the device that I never received.I am just so grateful now.