I got this message few days back:
"Today you received an extra invoice. This concerns an invoice for a trip that you have previously made, but which has not yet been charged. The amount on the invoice is correct, only the explanation was missing. We find that very annoying, and we apologize for that. We would like to provide you with more information in this email.
Why did you receive this invoice?
We have discovered that we have not invoiced you for a train journey you have made recently. It was our intention to charge these costs on your monthly Flex Invoice with a clear explanation. Something went wrong there: today you received a separate invoice that was not clear enough."
However I have not travelled in NS since Oct-2023 ! I moved out of Netherlands back to my home country on 20th Oct 2023. After clearing all my payments in Nov'23, I closed my ABN Amro bank account. So now that you are raisog this invoice against my travel more than 6 months back, I simply can not pay.