On how to fix this error we are sorry to have to tell you that as it is a problem on the game servers themselves there is not much you can do but be patient. Close the game for a few minutes or even an hour and come back later to verify that the problem has been fixed.
You can also access the game's support page and check their Twitter account or sign in with their server's status page so you can see what's going on.
That's all folks, what for now on how to fix the connection error in Fall Guys, just be patient that the developers are probably working to fix this error as quickly as possible.