Thanks to all. I figured it out. I was looking at History. I had to go back to Current Game (Ctrl-G) to get the Action tab to come back up. Hadn't noticed that UI nuance. Makes sense why it is does that. I just didnt know what I had done to make it go away. I relaunched the game to make it come back. But then I saw next time what had happened.
Apologies for the unnecessary question. Appreciate the quick responses.
BTW, I was playing AA50.

14962 works for me 