Corrupted packages/invalid keyrings during update

you will likely want to ensure your keyring packages are up to date first.

Try this

sudo pacman -Sy archlinux-keyring manjaro-keyring #installs keyring packages
sudo pacman-key --populate archlinux manjaro #updates keyring database with new files
sudo pacman-key --refresh-keys #Refresh all keys

It’s from my post over here,