GUI-Text changing script works in studio but breaks in-game. Why?

I have a problem with a script. The script works completely fine in studio, but does not work in game at all and the developer console shows no error messages. I've seen this problem happen frequently to others and I can't figure out how to fix it. I'm a beginner scripter, so I'm unaware of a solution to this. It is a regular script, not a LocalScript.

Finished = true
function onClicked(click)
if (script.Parent.Parent.Value1.Value == 0) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "1"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
elseif (script.Parent.Parent.Value1.Value == 1) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "2"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
elseif (script.Parent.Parent.Value1.Value == 2) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "3"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
elseif (script.Parent.Parent.Value1.Value == 3) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "4"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
elseif (script.Parent.Parent.Value1.Value == 4) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "5"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
elseif (script.Parent.Parent.Value1.Value == 5) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "6"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
elseif (script.Parent.Parent.Value1.Value == 6) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "7"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
elseif (script.Parent.Parent.Value1.Value == 7) and Finished == true then
Finished = false
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = "8"
wait(3)
game.Players.LocalPlayer.PlayerGui.TotalNumber.TextLabel.Text = ""
Finished = true
end
end
script.Parent.ClickDetector.MouseClick:connect(onClicked)

As what JackOfAllBlox stated, You should only use game.Players.LocalPlayer when you are running a LocalScript. So change it to a LocalScript and it should work.