What's this line mean?

Native speaker’s answer
Rebecca
Here, "not really" means "not truly," or not exactly the way it was. In context, they're saying that it might somewhat appear like things are normal, but they aren't in fact, or truly, the same. Ex: He seemed happy, but he wasn't really happy. He was, in fact, upset. Ex: This isn't really a real lion. It's just a toy one.