You've been using a lightning address in the NIP-05 field. This NIP-05 field is dedicated for a verification of your account and usable as a long term identity independent of your npub key you're using. This NIP-05 is totally optional (as everything else besides having a nsec key to sign your notes prior to pushing them to relays.

Because you didn't register/connect your npub with the NIP-05 you've entered the verification check on my client shows an error, which is the expected behavior.

A good service I'm using for NIP-05 myself is https://nostrplebs.com by #[6]