Express not reached

Hey guys,
I'm trying to send a post request to the node server but it's not able to reach. Can anyone please help me out as to why this is happening?
This is the code for server

const express = require("express");
const app = express();
const mongoose = require('mongoose');
const port = process.env.PORT || 4000;

require('dotenv').config();
app.use(express.json);

const uri = process.env.ATLAS_URI;
mongoose.connect(uri, {useNewUrlParser: true, useCreateIndex: true});

const connection = mongoose.connection;
connection.once('open', ()=>{
    console.log("Mongo db connected successfully")
});

const postsRouter = require("./routes/posts");

app.use("/posts", postsRouter);

app.listen(port, ()=>{
    console.log(`Connected and listening at port ${port}`)
})

And this is for post

const router = require("express").Router();
let posts = require("../blog.model");

router.route("/").get((req, res) => {
    posts.find()
    .then (users => res.json(users))
    .catch (err => res.status(400).json("Error" + err));
}) 

router.route("/write").post((req, res) => {
    const title = req.body.title;
    const content = req.body.content;
    const date = new Date();

    const newPost = new posts({title, content, date});

    newPost.save()
    .then(() => console.log('Post added!'))
    .catch(err => res.status(400).json("Error" + err));
})
module.exports = router;

Comments

[Shubham Verma]

Can you share the code?

[Shernz]

I've attached the code

[Ishan Srivastava]

Hey can you let me know two things, whats the value of port? And secondly if you make a testing route , like GET /test, and return a test JSON, does it work?

[Shernz]

4000 is the port value. And I also tried send() which is resulting the same