If you don’t have your band, your letter, or your hotel info, then yes.
You’ll have it with you for flying, so...
But if you’re thinking about a minor taking it alone you don’t need to worry about it. They know minors probably don't have ID. My 15 year old did just fine last month. He had the band and the letter. Lost the band at some point before checking in, but the letter was just fine.