Do you have a Trezor? If so it is so easy to sign the message. Downloading the software and signing the message is like 5-10 minutes!
That is a very small amount of Bitcoin to do it with but more airdrops will be coming soon! So it might be worth the time!
how can I sign the message using Trezor wallet ?
All right here ----> https://doc.satoshilabs.com/trezor-user/messages.html