Asked to make a second payment

I changed my debit order date from the 25th to the 1st of each month.

I called in February after my Feb-25 debit order. So, instead of March-25, I was debited on 1 April.

I am now told that I did not make a payment for March. I completely disagree with this.

How can a customer miss a payment on the 25 of the month, pay on the 1st and be told that they March debit order was not paid. It does not make sense.