I operate a new company in TPE,and lease 2 A320,2 A318.
Also set up 7 routes to GUM,KIX,OKA,HKG,ICN,HKT,MNL.
But only TPE-HKG have a good booking, other routes only have less than 10 passenger booking
I have set up a good transfer time
and all routes are over 80% loading in real-life, refer to the Taiwan Civil Aeronautics Administration's report
I hope to have someone help me. :D
Have you set up all these routes within the last 24 hours? If so, wait for 24 hours to see what happens. The game calculates passenger demand once per day, when the “passenger demand” time listed on the airport’s information page says. It sounds like you set up your TPE-HKG route before the demand calculation, but the remaining routes were created after the calculation cut-off point it could very well be that the few passengers that have booked on the other routes are transfer passengers.
If all your routes are more than 24 hours old, then check competition on those routes. There may be many planes flying them already, or your competitors may have nicer seats or better in-flight service.