Fuji Subaru Line 5th Station bus ticket

I have been trying to purchase Fujikyu bus tickets from Kawaguchiko Station to Fuji Subaru Line 5th Station. I read online that that Fujikyu will start selling the tickets online from May 17 2025 but have been unable to find them anywhere. I also downloaded Jorudan and Japan Transit Planner app but was not able to purchase the mobile ticket. Need advice on where I went wrong. Thanks.

Last year it was not until later in June when they announced the reservation website.
Note that there is no hurry. Tickets never sell out. In the worst case you can buy them also at the tickey office at Kawaguchiko Station. But the round trip ticket cannot be purchased on board of the bus. Regular one-way tickets, on the other hand, are simply paid on board of the bus.

Many thanks for your advice.