Invalid get index 'free_movement' (on base: 'Nil')

Hey guys,
i came back to my project from last year, but I cant start "Quick Play". In console I see this information:

SCRIPT ERROR: display_message: Invalid get index 'free_movement' (on base: 'Nil').
At: res://game.gde:9193

I tried to check everything in RPG in a box and some files, but I cant find this variable.
Where can I find this or what I can do?

I believe this was fixed on the Discord.

The error was due to a display_message request on startup before a map was being loaded.