I'm trying to book award ticket WAW-SFO on Finnair. after selecting the flight I'd like to purchase, I keep getting message:
"Chose a different flight or fare, We are sorry but at least one of the flights or fares you chose is no longer available"

This happens for all of Finnair flights, I'm trying for the last 3 weeks, at different times.
What could be the reason, and is there any way to overcome this ?


This is the message I keep getting, when trying to book AA award ticket on Finnair