Express GET request not working after adding authentication - node.js

Question

I'm stuck on this very simple problem and I don't know what I am doing wrong. I'm creating a simple RESTAPI with users and authentication. This is the GET request that I'm trying to run:
router.get('/users/me',auth ,async(req,res)=>{
console.log(req.user)
console.log('Entered the get request')
res.send(getUserData(req.user)) })
Basically, at the end of the authentication, I save the user fetched from the database into req.user object and then I send it to the client using res.send(req.user). As you can see in the code below:
const auth = async(req,res,next)=>{
try{
const token = req.header('Authorization').replace('Bearer ','')
const decoded = jwt.verify(token,'secretkey')
const db = req.app.locals.database
const user = await db.collection('users').findOne({
_id: decoded.id,
'tokens.token':token
})
console.log(user)
if(!user){
throw new Error()
}
req.user = user
next()
}catch(e){
res.status(401).send('Please Authenticate')
}}
The problem is that this authentication function is working perfectly fine. I have used it on other routes as well. But in this GET request, the authentication function runs (I identified this using many console logs) and fetches the data correctly. But it doesn't enter the get request once the middleware(auth function) has completed the call.
From POSTMAN, when I send GET requests, I get a 404 error and I have no idea why. I have literally spent hours trying to make sense of this. Please help me out if you know what might be the problem.
EDIT: So I was able to run the get request by moving the request above the following request that I also have in the same file:
router.get('/users/:id',auth ,async(req,res)=>{
const id = req.params.id
const db = req.app.locals.database
try{
const result = await db.collection('users').findOne({_id: id})
const userData = getUserData(result)
res.status(200).send(userData)
}catch(e){
res.status(404).send()
}
})
But now this request doesn't work. I cant figure out what positioning has to do with requests functionality. Can anyone please explain?