Very slow MongoDB Fetching when deployed on Vercel, but very fast on localhost

Good evening Mr Basir,

I was bought your latest Next.js Amazona course using mongo-db and tailwind on Udemy, but once I publish the project onto Vercel or Heroku or Netlify, the mongo-db fetching speeds becomes really slow.

It takes around 3-4 seconds to add a product to the cart.

Whereas, on localhost, it works very smooth and only takes about 70ms to add a product to the cart.

What could be the issue here- Mongo-DB or Vercel?

Hope that you can help me out here, as it is extremely urgent.

Kind Regards,
Aaryan Dua