express firebase serve POST/GET requests respond with 404 errors

I am trying to send POST/GET requests after using firebase serve, but this always responds in an error. I have tried many things like reinstalling node, using a backslash at the end of the url, using firebase deploy instead, resetting firebase.json, using ThunderClient in vscode instead of Postman, turning off ssl certificate for Postman, etc.

Screenshot of Postman

Here is my index.js file:

const functions = require("firebase-functions");

const express = require("express");

const app = express();

const Auth = require("./util/middleware");

// enable CORS

const cors = require("cors");

app.use(cors());

// can't use app level middleware :(

// app.use(Auth);

const { signup, login, logout } = require("./handlers/users");

const {

  getMyBoardsOverview,

  getLeaderboard,

  createBoard,

} = require("./handlers/boards");

// user routes

app.post("/signup", signup);

app.post("/login", login);

app.post("/logout", Auth, logout);

// board routes

app.get("/boards", Auth, getMyBoardsOverview);

app.get("/board/:boardId/leaderboard", Auth, getLeaderboard);

app.post("/board", Auth, createBoard);

exports.api = functions.region("us-west2").https.onRequest(app);
How many English words
do you know?
Test your English vocabulary size, and measure
how many words do you know
Online Test
Powered by Examplum