Error:404 Cannot POST /api/tests for Postman and Express - node.js

Question

I am creating a MERN stack based website, and was able to write GET and POST requests for two out of the three models I have created so far: users and profile. The latest one, tests, is giving an error of Cannot POST /api/tests. Here's the code:
server.js
const connectDB = require('./config/db');
const app = express();
//Connecting DB
connectDB()
app.use(express.json({extended: false}));
app.get('/',(req,res)=>res.send('API Running'));
app.use('/api/users',require('./routes/api/users'));
app.use('/api/auth',require('./routes/api/auth'));
app.use('/api/profile',require('./routes/api/profile'));
app.use('/api/tests', require('./routes/api/tests'));
const PORT = process.env.Port || 5000;
app.listen(PORT, ()=> console.log(`Server started on port on ${PORT}`));
Test.js
const TestSchema = new mongoose.Schema({
name: {
type: String,
required: true
},
domain: {
type: String,
required: true
},
activeStatus: {
type: Boolean,
required: true
},
questions: [
{
question: {
type: String,
required: true
},
option1: {
type: String,
required: true
},
option2: {
type: String,
required: true
},
option3: {
type: String,
required: true
},
option4: {
type: String,
required: true
},
answer: {
type: Number,
required: false
}
}
]
});
module.exports = Test = mongoose.model('test', TestSchema);
tests.js
const router = express.Router();
const { check, validateResult } = require('express-validator/check');
const auth = require('../../middleware/Auth');
const Test = require('../../models/Test');
const User = require('../../models/User');
// #route POST api/tests
// #desc Create or Update a test
// #access Private
router.post('/', [
check('name', 'Name is required').not().isEmpty(),
check('domain', 'Domain is required').not().isEmpty(),
check('status', 'Status is required').not().isEmpty()
],
async (req, res) => {
console.log("entered");
const errors = validationResult(req);
if(!errors.isEmpty()) {
return res.status(400).json({ errors: errors.array() });
}
const {
name,
domain,
status
} = req.body;
//build test object
const testFields = {};
if(name) testFields.name = name;
if(domain) {console.log(123); testFields.domain = domain;}
if(status) testFields.status = status;
testFields.questions = {};
try {
//see if test exists
// let test = await Test.findOne({name});
// if(test){
// return res.status(400).json({ errors: [{msg: "Test already exists"}] });
// }
//create
test = new Test(testFields);
await test.save();
res.json(test);
console.log(testFields);
res.send('Test Created')
} catch (err) {
console.error(err.message);
res.status(500).send('Server Error');
}
});
// #route GET api/tests
// #desc Get particular test
// #access Private
router.get('/', auth, async (req, res) => {
try {
const test = await Profile.findById(req.test.id);
console.log(test);
if(!test)
return res.status(400).json({ msg: 'Test not found' });
res.json(test);
} catch (err) {
console.error(err.message);
res.status(500).send('Server Error');
}
});
module.exports = router;
Things I've already tried:
Checked and rechecked the URL entered in Postman (http://localhost:5000/api/tests)
Set the URL type in Postman to POST
Made sure the URL was properly registered, and compared with working URLs and files
Even after this, nothing has worked so far. I am fairly new to this, so that might be the cause of my oversight, please do let me know if you can spot where it's going wrong.