Glad you're enjoying the game so well! Thanks for providing the save, also -- that made this one easy to spot. The planet in question has an AI Co-Processor on it, which interferes with your supply. You'll either have to destroy the co-processor (at AI Progress cost), or else you won't be able to use anything that requires supply on that planet. That's the conundrum of the co-processors -- but once you find all four of them and destroy them all, you'll not only get your supply back on those planets, but you'll get a net AI Progress gain. It's just an AI Progress loss until you destroy the last one.