Animation not working inside the symbol

Hi there! I am trying to do something very simple; i have a stars background and I have converted them into a symbol so they can shine in a loop. But the animation is not working. I have tried to use a 'on load' action but its still not working. Can anyone help me? Thanks!
stars.hype.zip (39.7 KB)

you'll need an action at the start of your symbol that continues the main timeline forward ...