unhappy about the service

On 28th I got a call from MTN to upgrade my package to SKY VIP for R1499.00 unlimited call and 25G data day and 25G night. I accepted and they said it will be activated in the next 72 hour. Today is the 4th and nothing happened. I phone them from Monday and every day they say they will phone me back but that also didn't happen. today me phone and now I need to sign a form and say what I package I want. they will send me the form via email but after an half an hour still nothing happened.