How do i make the lockfirstperson script work everytime?

i used this script:

script.Parent.MouseButton1Click:connect(function(GUI)
while true do
    wait(0)
game.Players.LocalPlayer.CameraMode = Enum.CameraMode.LockFirstPerson
if script.Parent.Parent.Visible == false then
    game.Players.LocalPlayer.CameraMode = Enum.CameraMode.LockFirstPerson
    end
    end
    end)

but it won't work for me an ideas on how i can make it work every time i click the gui button?