Why are `heroku pg` commands failing with "Couldn't find that add on"?
This message gets shown when the CLI can't verify you have access to these two resources, usually because the parameters being used to identify the database(s) are somehow ambiguous.
Instead of using
DATABASE_URL for example, you could try looking up the color URL using
heroku pg:info (this will be something like
HEROKU_POSTGRESQL_TEAL_URL) or the addon name using
heroku addons (this will be something like
flowing-example-1234). Using one of these more specific identifiers should help to resolve any issues in running the command.