Nedbank Merchant services keep on Debiting my account

Nedbank Merchant Services does not respond to my queries. They keep on Debiting my account although we agreed on 1 Month cancellation notice. I cancel my Credit Card Machine in September but still make me pay for the rental, double the amount I use to pay. Alicia Schoeman promissed to correct this but yet again, one month later I have to struggle to get through to any help. Alicia Schoeman don't even return my calls. Thandeka the Manager also don't return my calls. Please if you thinking of getting a Nedbank Credit Card machine, make sure you have time to struggle.