How can anyone run your postgres server in their localhost?

Question

We were in a hackathon and my teamate and me couldn't figure out why a app that i created with postgres with a client instance packet that takes my password and username couldn't be run on his device

We installed postgres on his device and all the other dependencies that I installed but we still couldn't start the database like why can't he see what's in my db why can't he run it on his device

Error in pgAdmin:

2025-02-23 23:36:30 IST LOG: database system was shut down at 2025-02-23 23:36:25 IST 2025-02-23 23:37:45 IST FATAL: password authentication failed for user "ue_a228" 2025-02-23 23:37:45 IST DETAIL: Role "u@_a228" does not exist. Connection matched file "C:/Program Files/PostgreSQL/17/data/pg_hba.conf" line 117: "host all all

Error in terminal:

[nodemon] starting `node index.js`
server runnin
error: password authentication failed for user "ue_a228" at Parser.parseErrorMess...time-capsule-2.0\backend\node_modules\pg-protocol\dist\parser.js:2
    at Parser.handlePacket (C:\Users\DELL\Desktop\time-capsule-2.0\backend\node modules\pg-pr otocol dist parser.js:122:29)
    at Parser.parse (C:\Users\DELL\Desktop\time-capsule-2.0\backend\node_modules\pg-protocoll dist\parser.js:35:38)
    at Socket.<anonymous> (C:\Users\DELL\Desktop\time-capsule-2.0\backend\node_modules\pg-pro tocol dist\index.js:11:42)