Stop debiting my account

I had Life cover, funeral cover and saving with Momentum, Last year I cancelled my life cover with them and only to find out they cancelled everything and I only noticed when I check my statement that there was no debit order went thru for them. I called them and I had to pay the mount from the time they stopped debiting. Same thing happened, they stopped debiting and I called yesterday what ****es me off is the bad attitude I got from their Agent, he said he's name is OJ and lying that they tried to debit my account twice and there where no funds, with the anger I had yesterday I told him to debit the money I owe the yesterday and still no debit order went thru. Momentum service is very bad, I regret the day I join them