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.comgpgsm: can't sign using
'email at gmail.com': No public key
$ gpg2 --list-keysgpg: checking the trustdbgpg: marginals needed: 3
completes needed: 1  trust model: pgpgpg: depth: 0  valid:   2
signed:   0  trust: 0-, 0q, 0n, 0m, 0f, 2ugpg: next trustdb check due
at 2028-03-15
[keyboxd]---------pub   ed25519 2025-05-11 [SC] [expires: 2031-05-10]
      XDuid           [ultimate] X <email at gmail.com>sub   cv25519
2025-05-11 [E] [expires: 2031-05-10]
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