hello, me and my friends have bought an interrail ticket and are planning our train journeys. our first journey is Zürich HB - Praha nl. on a night jet. since we already have tickets we only want to book a couchette to sleep during the journey, but we cannot find on SBB.ch that option, we can only buy a ticket + the couchette. on the interrail website is not possible to book a couchette.
