It might happen that the graphical software update will fail due to time not synchronized.

sudo nano /etc/systemd/timesyncd.conf and add a ntp close to you

FallbackNTP=0.ch.pool.ntp.org 1.ch.pool.ntp.org \
2.ch.pool.ntp.org 3.ch.pool.ntp.org

then restart it sudo systemctl status systemd-timesyncd

sudo systemctl restart systemd-timesyncd

sudo systemctl enable systemd-timesyncd

timedatectl show-timesync