Shocking service

Tried to do an upgrade and took an hour to be told at the end the system says the account is up to date but there is a hold asked them to call and sort it out he told me they don't take calls and the manager has to email them, he shows me the account history is perfect even worse on the Cell C app on my phone it shows Cell C owes me over R1300? I have a credit of over R1300???? They just waste your time. Left being told to come back in 2 days, are you serious been with them for over 23 years and this is the pathetic service I receive? Already canceled 1 of my 3 lines and took it to Vodacom perhaps it is time to port both my numbers as both are out of contract.