Terrible service!

I am so dissatisfied with Finchoice, firstly they have inexperienced and rude call centre agents who feels it's okay to speak over their clients and hang up on them when they still talking. Also failed to get a team leader or manager on the phone. I got a settlement letter from them, i settled the account and received a paid up letter stating the account is fully paid up and closed. Next thing I still have an outstanding balance, been calling since last week to resolve it with no luck, yesterday when I called I was told I disputed a debit order of which there is no record of that on my personal statement, I've sent it to them and I got no feedback, today a debit order went off causing unnecessary havoc in my account and I'm obviously going to have to dispute the debit order because they not going to reverse that debit order any time soon. The balance that I was owing before I settled and the current outstanding balance that I have now does not add up i am owing more than what it was previously which is not correct.