Good morning Alao, and welcome to our Community!

I have changed the title of your topic to make it easier to find. If your bank is not in the list, I suspect this is because it does not support iDeal payments and that you are changing the bank account for a NS Flex subscription. You need to pay € 0,01 via iDeal to confirm your new bank account. If that is not possible for you due to your bank not supporting iDeal, please contact customer service. They will gladly help you out with changing your bank account .

I want to Change my bank account and put the new one 

Hello LAMINSAMATEH949, Welcome at our community,

You can change it via Mijn NS. If you have the same problems as the topic starter then you need to reach our customer service.