I have found a 2nd class empty couchette travelling23/07/22 at 21.41Austerlitz to Nabonne 07.10 that I wish to reserve for my family ( of 5) but take the whole carriage. When speaking to the very helpful staff a SNCF they have reserved bookings over two fist class carriages as we have 1st class interrail tickets and informaing me it’s not possbile to take the second class as I will incurre a fee/fine on the train.
Any advise or insight would be much appreciated.
Thank you in advance