Apple Pencil

I purchased an Apple Pencil a couple years ago, recently I purchased a IPad Air. My Apple Pencil recently stopped working, so I tried charging it. It’s taking a very long time to charge when normally it charges very quickly. I tried disconnecting the Bluetooth and reconnecting the pencil and now the Apple Pencil cannot be recognized. I’ve tried restarting my iPad but the Apple Pencil still doesn’t come up in Bluetooth.