Trigger box light toggle error

So I’m following the some 200 video tutorial on youtube on how to use UE4 to create anything from simple models to scripts, and I’ve hit an odd problem that I can’t seem to find an answer to:

When I create a triggerbox that will turn on a light when I enter it, the light doesn’t toggle on but instead simply flashes once very fast and then stays off. The same thing happens when I exit the trigger volume. Any solutions?