Disgusting ...*****ing from the client

I am so sick and tired of MTN.. Each month they charge me a debit rejection fee...This was sorted out last year when I went onto a cash only basis..They have sent me countless messages to say I am on a Cash basis but still send through their debit order which they say are rejected..I can prove 100% there are no debit reversal on my bank account..Then when I don't pay the rejection fee they promptly cut my service off..If this is the kind of service that I am going to get then I will take my business elsewhere....What have they got working for them....I wish I didn't even have to put a * next to the review.....am totally disgusted with them