Bad Customer Service

I am a customer of cell c for the past 7 years i have 7 contracts with them i am thinking about canceling all of my contracts with them as i inquired about my early upgrade the call center guys said he would give me a call back in two hours its been 2 days and ive heard nothing. i did not expect this from cell c as its always a pleasure dealing with them i am really disappointed in the service i received from them.