How to create a schema in a Dev Database?

I’m using DigitalOcean App Platform and have a dev database with PostgreSQL 17 set up. As part of my planning, I’d like to create a separate schema to attain fine-grained access control.

I’m able to connect to my database using “psql” through the console of my web service.

my-db=> CREATE SCHEMA private;
ERROR:  permission denied for database my-db

I can only assume the user provided by DO does not have the permission to create a schema and I seem to be unable to grant it as well:

my-db=> GRANT CREATE ON DATABASE "my-db" TO "my-db";
WARNING:  no privileges were granted for "my-db"
GRANT

Is there anything that can be done about this?

Running \l shows that the owner of the database is doadmin, but I have not been giving the credentials for that user.