my new iPad has been "synching library" for the nook app for a day now. What's the solution?

Hello and welcome to Apple Support Communities, jacksrv6,

We understand your iPad has been showing syncing library in the Nook app. We'd be happy to help you troubleshoot.

Try restarting your iPad, since this usually resolves these issues: Restart your iPad - Apple Support

If the issue continues, reach out to the app developer: How to contact an app developer - Apple Support

Regards.