Rt-setup-database creates RT5 then fails

sbin/rt-setup-database --action=init

Or make initialize-database

sudo sbin/rt-setup-database --action=init
In order to create or update your RT database, this script needs to connect to your Pg instance on localhost (port ‘’) as postgres
Please specify that user’s database password below. If the user has no database
password, just press return.

Working with:
Type: Pg
Host: localhost
Name: RT5
User: postgres
DBA: postgres
Now creating a Pg database RT5 for RT.
Failed to connect to dbi:Pg:dbname=RT5;host=localhost;client_encoding=UTF8 as user ‘postgres’: connection to server at “localhost” (::1), port 5432 failed: FATAL: database “RT5” does not exist

RT5 does not exist prior to this command, it does afterwards - but shows as disconnected.

Any ideas?