Mtn

I have 3 accounts with MTN and I want to cancel the 3rd but it is a struggle they put me on hold for hrs but when the account is in arrears they can pick up my call and tells me that I can't cancel the account. But when is paid they put on hold for hrs. I have been sending emails regarding this but they are insisting that I must call until I get help from their retention department. This has been happening for 3 months now.