From that website at https://www.reisnordland.com/bus

Note: Bus tickets cannot be purchased earlier than 30 minutes before departure. We are currently developing a new payment solution and will make an announcement when it is ready.

You can buy tickets with:

·       Credit/debit-card on bus

·       Cash on bus (not Bodø)

·       Bodø City Center Terminal

·       Billett Nordland (app)

Thanks great help so our journey continues  

Thank you so much 

I did that bus journey in reverse (Fauske to Narvik) in February. There were very few people on the bus-there are several bus stops in both Narvik and Fauske so make sure you use the Nordland Reise app to pick the most convenient stops. Half price ticket for over 65s and their companions too! 
The journey was very scenic and included  ta boat trip. 

Thanks Newcastle Tourist, very helpful

Thanks so much for the info. I’m 65 so that’s really useful to know … thought the age was 67 here so very pleased . Also will look into the stops and get on/off at the correct one hopefully!