Why my SurfaceGUI Changing Text Script is Not Working?

It is a LocalScript which is under text object, it is supposed to work, but it doesn't!

local obj = script.Parent

while true do
    obj.Text = "Welcome to BioPlaza!"
    wait (7.5)
    obj.Text = "Take some snacks from our friendly Snack Machines!"
    wait (13.5)
    obj.Text = "We hope you enjoy your stay at here!"
    wait (8.5)
    obj.Text = "Go to the end of Hallway to find our donation chest, where you can donate 25 Robux to support us!"
    wait (12.8)
    obj.Text = "Remember! Failure, doesn't mean failure forever!"
    wait (7.4)
    obj.Text = "Remember! Keep trying untill you suceed!"
    wait (8.9)
    obj.Text = "Remember! Noone will give you anything for free! You have to earn everything!"
    wait (9.7)
end