How to clear/flush DNS cache for ubuntu 20.04

sudo systemd-resolve --flush-caches

The use below command to verify

sudo systemctl status  systemd-resolved


Below is the real outputs of above two commands

root@ubuntu2004:~# systemd-resolve --flush-caches
root@ubuntu2004:~# systemctl status  systemd-resolved
● systemd-resolved.service - Network Name Resolution
     Loaded: loaded (/lib/systemd/system/systemd-resolved.service; enabled; vendor preset: enable>
     Active: active (running) since Mon 2021-08-02 08:39:35 EDT; 29s ago
       Docs: man:systemd-resolved.service(8)
             https://www.freedesktop.org/wiki/Software/systemd/resolved
             https://www.freedesktop.org/wiki/Software/systemd/writing-network-configuration-mana>
             https://www.freedesktop.org/wiki/Software/systemd/writing-resolver-clients
   Main PID: 4624 (systemd-resolve)
     Status: "Processing requests..."
      Tasks: 1 (limit: 4617)
     Memory: 4.6M
     CGroup: /system.slice/systemd-resolved.service
             └─4624 /lib/systemd/systemd-resolved

Aug 02 08:39:35 ubuntu2004 systemd[1]: Starting Network Name Resolution...
Aug 02 08:39:35 ubuntu2004 systemd-resolved[4624]: Positive Trust Anchors:
Aug 02 08:39:35 ubuntu2004 systemd-resolved[4624]: . IN DS 20326 8 2 e06d44b80b8f1d39a95c0b0d7c65>
Aug 02 08:39:35 ubuntu2004 systemd-resolved[4624]: Negative trust anchors: 10.in-addr.arpa 16.172>
Aug 02 08:39:35 ubuntu2004 systemd-resolved[4624]: Using system hostname 'ubuntu2004'.
Aug 02 08:39:35 ubuntu2004 systemd[1]: Started Network Name Resolution.
Aug 02 08:39:55 ubuntu2004 systemd-resolved[4624]: Flushed all caches.
root@ubuntu2004:~#

A snippet of systemd-resolve man page:

       --flush-caches
           Flushes all DNS resource record caches the service maintains locally. This is mostly equivalent to sending the SIGUSR2 to the systemd-resolved service