Why does my Timer not work in a game?

gui = game.StarterGui.raidgui.raidtimer.raidtime timevalue = script.Parent.TimeValue maxtime = script.Parent.TimeValue.Value for i = 1, timevalue.Value do wait(1) gui.Text = tostring(maxtime-timevalue.Value) timevalue.Value = timevalue.Value - 1 end`

I used this script to make a timer and when I press run in studio, the gui has a working timer but when I enter the game it seems like when the server started the timer started counting but as soon as I, the player, entered it would stop. Im using StarterGui-ScreenGui-Frame if hat helps with the TimeValue in Workspace. Can someone help me make the timer work in a game?`