Weird error happening. Please help!

I keep getting this error every time i try to do this line of code:
Server:InvokeServer("Fire", "Fireball", {})

error:
Players.jilly3678.PlayerScripts.Replicator:9: attempt to call a nil value

Incase your wondering, yes I do have a variable for Server, and it is a remote function inside replicated storage.
also the replicator script is in starter player. i also get the same exact error for this line of code inside of it:
Effects[Set][Effects] (Data)

the data gets called like this later on in the first script:
Server:InvokeServer("Fire", "Shoot", {Charge = Charge, Cframe = Character.HumanoidRootPart,CFrame, endPos = Mouse.Hit.Position})

PLEASE help me!!!