Vodacom - Corporate Bully

Vodcom accounts departement are useless.

I was sent a quote for a cancellation on 5th Feb which I paid on the 6th Feb But the month-end invoice is now more than this and no-one can explain why, I just get told I have to pay or I will get handed over! I have phoned 18 times and have been made dozens of empty promises to get this resolved but no-one helps and everyone hides behind a different department being responsible. Sick of dealing with this customer unfriendly useless corporate bully.