Hi, our information relies on the timetable data provided by carriers. In case you see the message '’no price results found'’ we cannot get a price from the booking system for this train and therefore it is not bookable through us. It could be possible that it is because the train/connection is not running. Therefore, we advise you to check the website of the carrier for most updated information. Other dates do show the option to book so it looks like it is fully booked on the day you were searching.
As Backup there are direct Regionaltrains from Milan to Domodossola with connection for a train to Brig/Spiez/Bern 
these are reservation free
This is happening to me as well. If I went to buy a reservation ticket on the company website , how do I prove I’ve got a interrail ticket?
CanNOT book directly via that site.
Find and READ overveiw by seewulf on howtodo all by yourself and for cheaper too on the various railways-or sneeky ways around
Its never wise to ask something different again-and also read above: perfectly possible on slower times by suing local trains and change Domodossola
This is happening to me as well. If I went to buy a reservation ticket on the company website , how do I prove I’ve got a interrail ticket?
The advice from the experienced travellers in the community is to use other ways to make reservations than the Interrail/Eurail website. You can look at the guide in the link:
https://community.eurail.com/train-connections-reservations-47/how-to-get-reservations-105
If you, after having looked at the guide, have questions about how to make specific reservation, please give your travel details (departure date, time and route) preferably in a new topic, and you will get advice.
Please note that Interrail/Eurail charges an extra fee of 2 EUR per person and ticket in addition to the fee for the seat reservation.
