Issue calling functions from vercel

I have created a express API function. I was facing issue calling the function directly via its apprwrite URL on local env so I tried adding a proxy this worked on local env, but when deployed the code on vercel. I faced error: POST https://canteen-management-two.vercel.app/chat/user/yashTest 404 (Not Found).
I am even using AppExpress CORS Middleware but still facing such issue. Also added localhost, *.vercel.app as hostname as Platforms to my project.
FYI: I am to hit this endpoint using apprwrite's function URL via postman.

@darShan Can you help me with this?
Attached images of code. Please let me know if any more info is required.

I don't think this is related to cors.
How did you deploy your function at https://canteen-management-two.vercel.app? Does vercel allow using domain somewhere else?

I see that the direct url hit works - https://66700e5aef9b29ddc13f.appwrite.global/, its probably something with the proxy config you've defined.