Automatic
sudo pacman -S archlinux-keyring
Manual
https://forum.manjaro.org/t/signature-is-invalid/94500/16
sudo pacman -Scc. answeryto everythingsudo rm -r /etc/pacman.d/gnupgsudo rm /usr/share/pacman/keyrings/*sudo pacman-key --initsudo pacman -Sy archlinux-keyring- It is ok to have errors in that update. Just reply
Y sudo pacman-key --lsign-key 02FD1C7A934E614545849F19A6234074498E9CEEsudo pacman-key --list-keysto see if keys are[full]sudo pacman -Sy archlinux-keyringsudo pacman-key --list-keyssudo pacman-key --initsudo pacman-key --populatesudo pacman-key --refresh-keys. It is ok to have ALOT of errors here