This function expects a value of type widget_message->void, but this argument is an incompatible value of type void.

Trying to make a health slider but can’t manage to update the health. When I try to call UpdateHealth or UpdateShield I get this error:

This function expects a value of type widget_message->void, but this argument is an incompatible value of type void.

You subscribe to events with only the name and without the parentheses.
So Subscribe(OnHealthChanged)