to resolve postgresql in ubentu server

to resolve postgresql in ubentu server see detail as under

root@odoo14-dav-c-4-8gib-blr1-01:~# /etc/init.d/postgresql restart
[ ok ] Restarting postgresql (via systemctl): postgresql.service.
root@odoo14-dav-c-4-8gib-blr1-01:~# sudo -u postgres psql
could not change directory to “/root”: Permission denied
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket “/var/run/postgresql/.s.PGSQL.5432”?