That form has been broken for a long time now.

Just use any Dutch address, e.g. NS headquarters: Laan van Puntenburg 100, 3511 ER Utrecht

As long as you don't order a subscription with a new chipcard, nothing will be sent there.

Same goes for the phone number. NS will never call, so just use a 0, followed by any 9 digits, e.g. 030 751 51 55 (= NS customer service).

Good morning Ilke and welcome to the NS Community.

Unfortunately rvdborgt is correct, the Mijn NS system where you have to fill in an address and phone number only recognises Dutch addresses and phone numbers. You can fill in fictional Dutch ones and then adjust them later in your Mijn NS account, or contact Customer Service to have them change it for you.

Thanks a lot for you kind support and help.
I will follow your suggestion.
Thanx

Same for me. I live in Aken and wanted to order a new chipkaart in combination with Dal voordel, but the form only accepts Dutch address. Can I just buy this at a station?

You can't buy this at a station. You have to order first a personal OV-chipcard by www.ov-chipkaart.nl When you get the card you have to call the NS customerservice.

Yeah thanks, I did this already just a few minutes ago. The problem was with the form when you order the subscription. There is the option to order a new OV card in the same spot instead of using an existing one. This form only allows address from NL.

I have a German address in my NS account tho, because I created it in 2021.