Hello.
I have an Apply-to-each loop with a single Compose action in it. The Compose just writes an odata filter query to find a single item (ORDER_ID eq items('BuildQuery')?['ORDER_ID']), and the first action after the loop combines the Compose outputs using join(). It looks like this:

I want to condense that loop into a single Select action to save costs, enhance beauty, and reduce the chances of the flow tripping over itself (which is important since this flow must run every minute). Ideally, it would look like this:

I've already made this change for another flow that has the exact same structure, which references a different table. But now that I'm making the same change in this flow, with almost the exact same code, I get this error if I try to save: Flow save failed with code 'PropertyNotAllowed' and message 'The template action 'BuildQuery' at line '1' and column '18889' is not valid. The property 'actions' is not allowed on action type 'Select'.'.
I've already tried closing the flow editor and re-making the changes, sometimes with extra spaces in case it just doesn't like a specific spelling, but it refuses to budge on this despite allowing me to do it in another flow with the same structure. (the accepted Select statement is below)

What do I do from here?