Two things to try:
- Remove the current ‘custom flight’ saves and restart the sim: I cannot load any different airport and plane - always the same airport and same aircraft - non ascii windows 10 account name - #77 by BlondeAcrobat62
- Do you have any non-english characters in your windows username? That can sometimes be an issue:
I cannot load any different airport and plane - always the same airport and same aircraft - non ascii windows 10 account name - #64 by CaptKennintong