Don’t know where are you trying to book because you didn’t tell but there’s availability here: www.entur.no. 

But there’s track engineering going on that day so you need to take a bus from Voss to Bergen.

Thank you for answering me!

Sorry you're right, I tried on rail ninja and vy.no

I tried on entur too but there's no availability.. I tried using different time too

I’m sorry, when I try to really book it, I do get a “train is sold out message”, too. Just the bus is available.

Do you think I have any chance maybe later? The departure is more than 60 days from now so I don't know if there's any chance that there will be new tickets later.. I didn't think it would have been sold out so fast

The main question is if the train is really sold out or if it’s not open for booking yet because of the track engineering. But the message given is “sold out”. And the trains before the closure going directly to Bergen the day before do show the same message.

Possible turnaround: Go by train from Oslo to Stavanger; that one is available. And from there by bus to Bergen. It’s much slower, but: the train journey is really an interesting one and even the bus journey; the bus goes on two ferries on this trip and the bus is available for 199 NOK. Of course this is a full day yourney, too, but an interesting one. There is a night train to Stavanger, too (that has availability) at 22.25 from Oslo - would mean 13.10 in Bergen by connecting bus.

There being engineering works at that time would suggest that it may not be the train being sold but it not being available yet.

You could message or call intur and see if they have any further information.

BTW “rail ninja” or any site that has any connection to this is a scam, do not use under any circumstance.

Thank you!! You've been very kind! I'll wait some days to see if something changes then I'll try what you suggested!

For the train from Oslo to Stavanger it’s possible to reserve at www.entur.no (don’t forget to add your railpass) before searching and the bus is available here: https://www.nor-way.no/en.

I'll do it! Thank you for your suggestions, I didn't know about rail ninja