Retentions/Cancellations

Cancelling a contract with MTN is like trying to get released by a crocodile! It cannot be cancelled at a branch. Then it takes anything up to 5 days to get a response from the relevant department. They calculate and give you the payment to be made and after making it, you must call THEM within 24 to 48hrs to tell them what they already know (i have received an SMS saying it has been received!). When calling the relevant number, nobody answers the phone. After listening for more than 10 minutes to endless adverti*****ts, I gave up! They take 5 days to answer an email, but I must call them between 24 and 48 hrs! What has happened to Customer Service?