Just update /etc/pacman.conf as follows
#[core-testing]
#Include = /etc/pacman.d/mirrorlist
[kde-unstable]
Include = /etc/pacman.d/mirrorlist
[core]
Include = /etc/pacman.d/mirrorlist
#[extra-testing]
#Include = /etc/pacman.d/mirrorlist
[extra]
Include = /etc/pacman.d/mirrorlist
$ sudo pacman -Syu and relogin to Arch instance
