At 7 months old, and still very a much a puppy, they are still growing/developing and 'data processing' so much information about the world and how they fit into it, and how to interact with it, which is very energy consuming, so it is quite normal (and necessary) for them to sleep several times a day. If she prefers to nap in the crate, where she feels comfortable and safe, and is less likely to be disturbed - I would suggest let her sleep there and it may be that when she matures, she will choose to sleep elsewhere.