error:
sudo pamac update
...
Apply transaction ? [y/N] y
Resolving dependencies...
Checking inter-conflicts...
Download of archlinux-keyring (20210820-1) started
Download of archlinux-keyring (20210820-1) finished
Checking keyring... [1/1]
Checking integrity... [1/1]
Loading packages files... [1/1]
Checking file conflicts... [1/1]
Checking available disk space... [1/1]
Upgrading archlinux-keyring (20210802-1 -> 20210820-1)... [1/1]
==> Appending keys from archlinux.gpg...
==> Locally signing trusted keys in keyring...
==> Importing owner trust values...
==> Disabling revoked keys in keyring...
gpg: checking the trustdb
gpg: key 786C63F330D7CB92: no user ID for key signature packet of class 10