Getting an empty response from express+NodeJS with POST request

Question

Learning nodeJS so pardon the beginner question I would like to create API endpoints for methods to post and get data from my server.

However, whenever I try to create a new entry with these endpoints on postman my response only returns the id associated with the entry, whereas I should be receiving the id,name and bio. Secondly, I have a validator that should check whether or not a name and bio have been entered before returning a response (if either of these have not been entered, the response should be an error message). When I added my if else statements I only receive the error message regardless of whether I sent a bio and name

Here is my code (model.js):

const insert = ({ name, bio }) => {
  const newUser = { id: getId(), name, bio }
  users.push(newUser)
  return Promise.resolve(newUser)
}

and my endpoints

const express = require('express')
const Model = require('./users/model')
const server = express();
server.use(express.json());
server.post('/api/users', (req, res) => {
    let { name, bio } = req.body;
    let model = req.body;
    if(name && bio) {
        Model.insert(name,bio)
            .then(elem => {
                res.status(201).json(model);
            })
    }
    else {
        console.log(name)
        res.status(400).json({ message: "Please provide name and bio for the user"})
    }
})

FYI: My console.log returns undefined