Ntpd drifting, very fast

I have to run stop ntp/ntpdate/start ntp every day, since my Laptop (ThinkPas AMD64 Rhyzen, Ubuntu 20.04) looses half an hour a day

Here is my ntp.conf (almost the default):

driftfile /var/lib/ntp/ntp.drift
leapfile /usr/share/zoneinfo/leap-seconds.list

statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable

server aragorn.groumpf.org iburst
server numenor.groumpf.org iburst

restrict -4 default kod notrap nomodify nopeer noquery limited
restrict -6 default kod notrap nomodify nopeer noquery limited

restrict 127.0.0.1
restrict ::1

restrict source notrap nomodify noquery

I'm not a Linux newbie, but simply cannot see what's happening

Thanks for help

Xavier

EDIT : the requested additional info, clock has been ntpdate'd just now:

[xavier@imladris ~]$ cat /var/lib/ntp/ntp.drift
-0.189
[xavier@imladris ~]$ timedatectl status
               Local time: Wed 2021-11-03 08:58:59 CET
           Universal time: Wed 2021-11-03 07:58:59 UTC
                 RTC time: Wed 2021-11-03 08:16:53
                Time zone: Europe/Paris (CET, +0100)
System clock synchronized: no
              NTP service: n/a
[xavier@imladris ~]$ ntpq -pn
remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
+176.31.180.205  193.52.184.106   2 u   35   64    1   15.545  309.431 255.807
*192.168.100.144 193.52.184.106   2 u   10   64    3    0.166  490.224 445.668

I suggest you remove ntp:

sudo apt remove ntp

and install systemd-timesyncd (which should be installed by default on all new installations):

sudo apt install systemd-timesyncd

After that, check with

systemctl status systemd-timesyncd

that "systemd-timesyncd.service" is "active (running)" and with

timedatectl status

you should see something like:

...
System clock synchronized: yes
              NTP service: active
...

^{See also this.}

I finally gave up with ntpd, installed chrony successful

Thanks to all who helped

Cheers

Xavier