Unexpected debit order

I think when I took the policy I stated that you can take the money from my account on the Last day of the month because I'm getting paid on the last day of the month. I don't know why you had to deduct money from my account on the 24th of may because that money was meant for something else. I tried to reverse it but I couldn't. Please reverse the money and deduct only on the day we agreed on.