How about, can you connect it to your computer and see if that breaks the loop? If that doesn’t help but you can connect to your computer, I wonder if you might benefit from running an error check (chkdisk) on the player and/or, if needed, reformatting the player from your computer.
If none of the above helps (but you might want to try the reformat as a last effort, if you have content you want to keep on your player), I wonder if you might need to turn the player on and let it run down, charge it again, and then try it.
Sorry–just doing some brainstorming here, as to solutions that have worked in the past . . . .