Hi A.A. Sikder,

Invoices are always automatically withdrawn from your bank account. Only if this is unsuccessful you'll receive a payment link by e-mail. So your manual payment was probably from the previous month.

Safely ignore what that cost counter in the NS app (or Mijn NS website) says, both for the amount and invoice date. It’s notoriously broken, for years already!

The accept e-mail went through, so you’re good to go. That was a first reminder for an unsuccessful auto-debit.

If you want to be auto-debited from a different IBAN, see https://www.ns.nl/en/mijnns#/producten to change it (transfer € 0,01 for confirmation, you have iDeal)