You will probably need to follow it with a Refresh Window [ flush cached join results ] script step.
How do you set that up. I have never done this before.
I would need a LOT more information to properly advise. It is normal that you won't see immediate change on your layout until you click until you perform an action. But try this:
While in layout mode and while on the layout does not refresh, select Insert > Button. Scroll down to bolded WINDOW section and select Refresh Window and check 'Flush cache...'. Say OK and type button text such as refresh.