timedatectl- NTP Sync cannot set to yes [duplicate]

I tried so much different things of installing ntpq or other stuff but nothing works.

I dont can change it to yes. I hope someone can help here.

I had Ubuntu 16.04 This is my terminal output of the Command timedatectl

      Local time: Tue 2017-06-27 20:52:45 CEST
  Universal time: Tue 2017-06-27 18:52:45 UTC
        RTC time: n/a
       Time zone: Europe/Berlin (CEST, +0200)
 Network time on: yes
NTP synchronized: no
 RTC in local TZ: no

Also tried this tutorial: https://www.digitalocean.com/community/tutorials/how-to-set-up-time-synchronization-on-ubuntu-16-04

But when i make sudo timedatectl set-ntp on it only changes Network time on: yes/no.

Also installed ntp. But from the command sudo ntpq -p i get this error

ntpq: read: Connection refused

Solution 1:

When the clock is too much desincronized (more than 3 seconds?) it won't get update automatically. In order to force it manually:

sudo service ntp stop
sudo ntpd -gq ← here you can see it's getting sync
sudo service ntp start

Confirm everything's ok
timedatectl
Better explanation and all the credit here

Solution 2:

After installing ntp

sudo apt install ntp

in the output of timedatectl

NTP synchronized: yes

the time is immediately automatically synchronized.