Extra Billing and Free Data Issues

I had upgraded my contract with Mbali at MTN on the 19th of October 2015. By right the contract and new plan as well as the 30GB free data should have started on the 1st of November 2015. which by the 6th did not start as yet, i had continuously left messages and emails which they did not get back to, i then logged a query with MTN call center. The free Data of 30gb valid for 30days was loaded to my number, although the new contract plan was not activated (which put me out of pocket) 46days late the contract plan was activated and the 30gb was lost and it was only 20day of the data being active. Anyway this morning i went to sort the situation out at the branch and waited for more than two hours only to be told that a query will be logged and you will have to wait. I then went back to speak to the Manager Gavin and he then ignore the fact that i was there waiting for 1.5hours and sent someone who **** that he was Gavin and was told there is nothing they can do. this is just an inconvenience, i wish to give my phone back to MTN and cancel the contract, but that is not possible as well. My ***... ANGRY AND READY TO TAKE MTN DOWN. THIS IS DAMN RIDICULOUS. WORST SERVICE EVER