Worst service ever from all the cell phone service providers out there!!!

I have spent 6 hours on hold for the sales team to assist with upgrading my cell contract. Twice I was connected to agents. I start the process for the upgrade with the fist person. After explaining what I want she told me it is not possible. I asked to speak to the manager. The lady said the manager will call me in 5 min it is now 7 hours later. I called back. On hold for 2 hours before the call was answered. While talking to kwamele the sales agent she just put the phone down in my ear. She didn't call back and the manager has not called me neither. This is shocking from a service provider that you pay every month. But they will disconnect you if you pay 5 min late.