First of all, remove rex's Container plugin from your project, and WebStorage too. These are very old, long deprecated plugins.
The problem is not with the containers, but with wrong usage of "Else" in event 39. "Else" doesn't mean "all other instances". It means that if previous event didn't pick any instances, only then the "else" block will be triggered.
You need to remove "Else" and change the event to this:
Hitbox is NOT B -> Shield set invisible
(add "Hitbox is B" and then invert it)