Endless Debit Orders for paid up account

Having a terrible experience. FinChoice is eating my money every month with debit orders that they won't let me cancel after having paid up their loan. I spoke to them multiple times and the consultants keep telling me they will give me a call so that they can process the cancelation for these debit orders.

Someone help me, how do I escalate this? I was even thinking of closing my account completely but that would cause so much inconveniences.