Why am I receiving this - role postgres does not exist?

Running PostgreSQL server on Void Linux. After installing ran initdb as OS user 'postgres':

[user@host]$ sudo -u postgres -i
$ initdb -D '/var/lib/postgresql/data'

Received output:

creating directory /var/lib/postgresql/data ... ok creating subdirectories ... ok selecting default max_connections ... 100 selecting default shared_buffers ... 128MB selecting dynamic shared memory implementation ... posix creating configuration files ... ok running bootstrap script ... ok performing post-bootstrap initialization ... locale: Cannot set LC_MESSAGES to default locale: No such file or directory ok syncing data to disk ... ok

WARNING: enabling "trust" authentication for local connections You can change this by editing pg_hba.conf or using the option -A, or --auth-local and --auth-host, the next time you run initdb.

Success. You can now start the database server using: pg_ctl -D /var/lib/postgresql/data -l logfile start

I've then proceeded to create the service, grant the ownership to 'postgres' and start it:

[user@host]$ ln -s /etc/sv/postgresql /var/service
[user@host]$ sudo chown postgres: /var/service/postgresql
[user@host]$ sudo sv start postgresql
[user@host]$ ls -l /var/service/postgresql
lrwxrwxrwx 1 postgres postgres 18 nov   2 17:05 /var/service/postgresql -> /etc/sv/postgresql

Running:

[user@host]$ sudo -u postgres psql ...

will give me the following error:

psql: FATAL:  role "postgres" does not exist

I've tried granting ownership of /etc/sv/postgresql to 'postgres', but no luck.

These were my sources:

https://wiki.voidlinux.eu/PostgreSQL

PostgreSQL error: Fatal: role “username” does not exist

I do not know what to do next.

EDIT: Stumbled upon psql: FATAL: role “postgres” does not exist. Cannot run psql -l because I get the same error, no matter which user I run psql as.