gpgsm: can't sign using 'email at gmail.com': No public key

[Nick]

I can’t sign using my public key which --list-keys shows. Does anyone have a solution or pointers on how to debug this further?

Is it because --list-keys shows 0 for signed keys?

$ echo "signme" |gpgsm -s -u email at gmail.com <mailto:email at gmail.com>
gpgsm: can't sign using 'email at gmail.com <mailto:email at gmail.com>': No public key

$ gpg2 --list-keys
gpg: checking the trustdb
gpg: marginals needed: 3  completes needed: 1  trust model: pgp
gpg: depth: 0  valid:   2  signed:   0  trust: 0-, 0q, 0n, 0m, 0f, 2u
gpg: next trustdb check due at 2028-03-15
[keyboxd]
---------
pub   ed25519 2025-05-11 [SC] [expires: 2031-05-10]
      XD
uid           [ultimate] X <email at gmail.com <mailto:email at gmail.com>>
sub   cv25519 2025-05-11 [E] [expires: 2031-05-10]

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