Hi…,
Welcome.
That normally indicates you haven’t started MSFS or don’t have a connection between MSFS and Simlink. If you have MSFS running and still have the error, I suggest you reinstall the latest Simlink.
Re Charts In Game Panel login please see Continually asking for sign-in in MS2020 Beta and Having to verify account every time? - #4 by Seth2413
Cheers
Ian