Hi
it doesn't work because you aren't checking if the thing is NULL or Blank or has a value, you are just comparing a value to true.
Change it to this
use the expression empty do not TYPE the word empty
delete custom messgae on the left
click in, when the pop up shows up go to the Expression tab
type empty() and it should come up and you can select the expression
Now with the window still open click on the Dynamic Property Tab
click the mouse between the two ()
now find the Custom Message Column and place that there
Change the middle to be is not equal to
and leave the right as the true expression.
Now it will return true or false on the left if its Empty
So you want
IsEmpty is not equal to true
So that in your Yes side, it means it was NOT empty and do your action 1
And on the No side, it was empty so do your action 2