Unauthorised debit deduction and random debit dates

I have opted in for a debicheck last year to ensure payment of cartrack account. My debit date is the 26th and as per debicheck you can track it three days before the time. last month my debicheck went off on the 26th and on the 7th of March they attempted to deduct an unauthorised amount of R850 which i reversed . I get my child maintenance on the 20th. I have a R24 in my account and R1100 maintenance was paid. Car track took R1119 from my account. Now debicheck you track 3 days before deduction date!!!! This is against the law and against what i agreed . If i do not hear from you i will be taking this to my lawyer, i have seen your reviews and you do not respond. I will give u 7 days thereafter i will proceed with legal proceedings where i will formally lay a case of ***** against you.