I am not sure, it could be that the cowgirl doesn't have milk, or something else. It could also be a bug, but I'm not able to replicate it.
I tested just now, and I wasn't able to replicate it. The feeder should be able to feed regardless of what the milker is doing. Are you able to post a gif or a screenshot of what's happening?
Edit: could it be that the cowgirl is maxed out on nutrition? If the cowgirl has something like 10k nutrition, she will stop consuming food, so it will stay in her inventory and the feeder won't be able to give her anything more.
Ah I see. The care robot requires power to function (in general all structures with a little lamp require power). You can give power to structures with a transmitter pylon or similar.
Edit: there is a bug here tho, and it is that the milker can milk once without power, which I should get around to fixing.
The framerate is fine, its just that i was recording it. Also the structure does have power but it still isnt feeding the cow girl
Edit: Nevermind! I WAS due to there not being a transmitter pylon nearby, the bug where the milker worked without electricity was just making me think I had power. Thanks so much.