game.ReplicatedFirst:RemoveDefaultLoadingScreen() is searching for an Image that doesn't exist?

I am trying to create a loading screen, and am encountering a very strange error that has me very confused.

Currently I have a localscript named LoadingScreen inside of ReplicatedFirst that will copy a screengui into the playergui. The main problem is that when I try to remove the default loading screen, with this at the top:

wait()
game.ReplicatedFirst:RemoveDefaultLoadingScreen()

I get an error only inside of a live server (works fine in local server and pressing play in roblox studio) that says

Image is not a valid member of ReplicatedFirst
Stack Begin
Script 'ReplicatedFirst.LoadingScreen', Line 2
Stack End

I can't figure out why I am getting this error and how to fix it... Help!