Set Visibility for a Widget doesn't work!

Development Programming & Scripting Blueprint
1

I’m working using the same xample found in the learning center and regarding the inventory system.
I have properly got GameHUD from the wigdet I have to show/hide. It works even setting the later variable but not the property “SetVisibility”
Same situation in the learning example… what’s worng?

2

Found the problem sorry… I had to set a variable also!