You can't travel with a 1st class reservation if you have a 2nd class pass so you need to change your reservation.
If you have an Interrail pass you don't need a ticket as the pass is your ticket so I hope that you mean that you made a reservation at sj.se and not bought a ticket.
Thank you Anna! Yes, I mean that I made a reservation at sj.se. Do you know already this site? It showed that I could have added my pass and select a timetable and also first or second class. It is strange that It allowed me to made a reservation for the first class if it was not possible, isn't It?
It works maybe that it is not possible only on interrail.eu, but in this scandinavian site it is possibile?!
Anna IS fra Sverige and has some contacts with SJ=the TrenSweden like TrenItalia.
The proper way to make a RES on sj.se is to open the PRIO window and scroll down till you find ´INter/EUrail´ and add the pass cover nr (you have to generate that from the site if you hold a mobile pass-it is printed on backside of paper pass.
NOT all trains can be RES via sj-as some are run by VY, originally the Norske TrenNorway.
In general forget the app etc rom INterrail-you can also save money and trouble (no paper post to send) by using other means-tjhe national train sites. Ciao e buone viaggio.
Thank you Anna! Yes, I mean that I made a reservation at sj.se. Do you know already this site? It showed that I could have added my pass and select a timetable and also first or second class. It is strange that It allowed me to made a reservation for the first class if it was not possible, isn't It?
It works maybe that it is not possible only on interrail.eu, but in this scandinavian site it is possibile?!
Basically, the website doesn't know what class your pass has.
@Maddalena la Micela
It is your responsibility to buy a reservation for the correct class. As @rvdborgt writes, the website of the national railway doesn't know which type of pass you have.
No matter if you make a reservation at sj.se, bahn.com or ÖBB you need to select the correct class.
