I can’t find a way to book a seat reservation on this direct train (EC19 Zurich Milan) for 11 June 26 or any other dates that I’ve tried over the next three months. I’ve tried the Interrail site, RailEurope, obb, cd, …The Interrail App says: No price results were found. Pass holder reservations may be sold out for this connection, but there are other ways to check for available seats—more info below our timetable.I know I can get other non-direct trains but interested to know why this one doesn’t seem to be available.