Hi Indie2040 and welcome to our Community!

That sounds like an odd problem. Could you indicate what error message you are getting or what happens when you try to order a ticket for 4 persons? It is working flawlessly on my end.

A screenshot of the error message or of the place where you get stuck would be helpful (wipe out any personal information). Also a description of any action you did before an error message appeared.

Excuse me, my English is not so good.

 It is not possible to make a booking a group ticket. Why not.

every time the same. Where is the mistake?

The problem is not the number of passengers, but the ö in the name of one of the passengers. I would suggest replacing it with oe.

Also, note that you might not want to buy this ticket this far in advance, since it cannot be refunded if the trip would not go through for some reason.

Thank you, I have tried it. It was the name with ö

Tausend thanks 

That means we've found a new bug. Would ë also trigger this? That does appear in Dutch names…

Long time since I bought an e-ticket, but I can't remember having issues despite the ë in my first name.

(The ë works fine in most NS systems anyway, didn't have to change it to an e in MijnNS)

For tickets, NS only need the first letter of your first name.

That's why I also mentioned the other NS systems. Haven't ever seen surnames with an ë by the way.

Can’t think of one with ë or é but names like Böhmermann are common, so should be accepted (or corrected automatically)

https://soundcloud.com/sleutelstad/2016-03-11-edwin-bohmermann-ns-over-toegankelijkheid-poortjes-leiden-centraal (wink @Momo, die persoon kennen we toch?)

Daniël Daniël