Update error keyring

sudo pacman -Syy
sudo pacman-key --refresh-keys
sudo pacman-key --populate archlinux manjaro
sudo pacman -Sc

Or:

sudo rm -r /etc/pacman.d/gnupg
sudo pacman-key --init
sudo pacman-key --populate archlinux 
sudo pacman-key --refresh-keys
sudo pacman -Sy gnupg archlinux-keyring 
sudo pacman -Sc

Or (e.g. for EndeavourOS):

sudo pacman -Syy archlinux-keyring endeavouros-keyring
sudo pacman -Su

Source:

• https://forum.manjaro.org/t/manjaro-is-unable-to-update-gpgme-keyring-errors/96941
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