error: database "dbName" does not exist Node.js PostgreSQL

I'm just starting with Node.js and I'm following this tutorial https://dev.to/glaucia86/developing-a-crud-node-js-application-with-postgresql-4c9o

when setting .env file as suggested

DATABASE_URL=postgres://{db_username}:{db_password}@{host}:{port}/{db_name}

so

DATABASE_URL=postgres://vinnytwice:pass@localhost:5432/fixit

I start the server with npm start command when using Postman to send a Post request I get they error in console:

vinnytwice@Vinnys-iMac fixit_server_node % npm start

> [email protected] start
> node server.js

App executing to port  3000
error: database "vinnytwice" does not exist
    at Parser.parseErrorMessage (/Volumes/ProjectsSSD/FixitServer/fixit_server_node/node_modules/pg-protocol/dist/parser.js:287:98)
    at Parser.handlePacket (/Volumes/ProjectsSSD/FixitServer/fixit_server_node/node_modules/pg-protocol/dist/parser.js:126:29)
    at Parser.parse (/Volumes/ProjectsSSD/FixitServer/fixit_server_node/node_modules/pg-protocol/dist/parser.js:39:38)
    at Socket.<anonymous> (/Volumes/ProjectsSSD/FixitServer/fixit_server_node/node_modules/pg-protocol/dist/index.js:11:42)
    at Socket.emit (node:events:369:20)
    at addChunk (node:internal/streams/readable:313:12)
    at readableAddChunk (node:internal/streams/readable:288:9)
    at Socket.Readable.push (node:internal/streams/readable:227:10)
    at TCP.onStreamRead (node:internal/stream_base_commons:190:23)

What am I doing wrong ? Many thanks.