Not enough info to even guess what might be wrong, but I'd assume it's defective and I'd try with another key as well. I wish you good luck with the next Yubkey

Not enough info to even guess what might be wrong, but I'd assume it's defective and I'd try with another key as well. I wish you good luck with the next Yubkey you get! :) Btw. this is the first time I've read on a public forum that someones Yubikey is defective, they are really well made and I didn't manage to break one via regular use and bad maintenance.