you mean the storage in the domain? you have to check it immediately after you milked, it will be sold tomorrow.
Yes, the domain storage. When i finisht milking in the top left side comes an infobar. At the first few milkings there was always 1l or so but now 0l. When i'm looking at the storage right after the milking, there is no milk. Same with Aurora. Not really a thing but i like the vision of having milk from "my cows". ;)
Edit:
Okay. I played a few minutes after this post and bam, 2lL from Aurora. Strange. Yesterday zero liters from Bianca and Aurora and no money from milking.
The game is time based and you have to do things around town to get the milk gauge to fill. There is a glitch right now on the mayor that makes it so you can milk her twice without going through the animation. Play the normal animation and the skip button will remain in the corner. If she is full you get 20 instead of 10.