Password authentication failed to database on Official VM script

Nextcloud version: (Official VM)
OS: Ubuntu 22.04.2
Apache: 2.4.52
PHP: 8.1.2-1ubuntu2.11 (cli) (built: Feb 22 2023 22:56:18) (NTS)

I’ve just finished setup of Nextcloud on a clean install of Ubuntu Server using the official VM script from the nextcloud github repo.

Nextcloud itself is working normally although I am trying to test access to the database.
I attempted to connect through Adminer.
System: PostgreSQL
Server: localhost
Username: ncadmin
Database: nextcloud_db

It shows the error:

Unable to connect to PostgreSQL server: connection to server on socket "/var/run/postgresql/.s.PGSQL.5432" failed: FATAL: Password authentication failed for user "ncadmin"

I’m not sure if Adminer expects the database username and password or the credentials for the postgres linux user so I’ve tried both with no success.

I see the same error when attempting to access from SSH.

sudo -u postgres psql nextcloud_db

Postgres and Adminer were configured automatically by the install script so I would expect it to work out of the box.

Normally I would look through but it shows a 502 Bad Gateway error currently.