Exorbitant debit order threatened by Woolworths Financial Services

I received an sms from Woolworths informing me that I'm going to be debited an amount of R 1 663 tomorrow (FSP/NCRCP49) my last debit order went off on time for the full amount of R744,90, no amount missed. This is exorbitant and an abuse of my debit order which I have made willingly to Woolworths, however if this is not reversed before tomorrow and confirmed with me before 1PM I reserve my right to reverse this amount and pay in person moving forward. I have to tried to make use of your toll free number and after using R100 airtime, your agents Wendy and Zondi act as if they can't hear after asking you the questions, whereby you can hear them but they are fully audible. If I don't hear from you by 1pm today, this serves as notice of termination of my debit order with Woolworths. Further to this I must add that I have not heard positive feedback regarding Woolworths financial services and I await to see how my complaint will be handled.