Save The Children — Save the Children amount debited my amount

I have agreed to donate 500 rupees for 6 months by Dec 2019 and they have debited that amount on any day of the month. After 6 months completion also they have debited too rupees on 9th of Nov 2020 and that time my account does not have sufficient fund due to which RBI charged insufficient fund return charges of 590. Really annoying me, I have requested them to fix a date for amount debit and let me know but they never properly responded. Whenver I raised a request regarding this they are keep on saying that they 'll check with Delhi team and get back to me but that person revathi never did it. Even now I got a same answer. Even if we interested to donate in future this kind of issues will make us to ignore them. I do not need want any transactions with save the children. Please help me and take necessary action in them.