In v1.0.52 I ran into a bug where very late in the game my two largest planets got stuck with 0 Production, even after canceling all "inifinite" production items. And adding new ones (or the old ones), would send the Production into the negatives. I'll see if I can grab a save once I'm stationary again.

Edit: I didn't see it until after I posted this, but it looks like the same bug noted here: https://www.games2gether.com/endless-space-2/forums/114-bug-reports/threads/26161-blocked-construction?page=1

I have a save game, where it happens. It should be reproducable (in my case it is by reloading save).

On system ZHAEN I can put any building in my queue, but it wont start to produce by giving me the message, that an infinite construction is in my queue. There is not, it's empty, apart from one building I want to produce...

Endless Building bug.zip