I'm new to pumping and just got my first batch of frozen milk out to give my son but it wasn't frozen! All of the other bags of milk are frozen, it's only the 2 bags from my first pumping session that aren't. They're kind of partially frozen but mostly liquid. Has anyone else experienced this? I found some posts in other forums about it but no one seems to have found an answer, and the posts are so old that I can't contact the moms that posted them. For now I'm just throwing them out and using the next bag, but I'm hoping to find an answer so it doesn't happen again. What a waste!