a nestjs deployed in nestjs, but got error "Target "/" could not be parsed"

[zshnb]

Page to Investigate

https://domain-price-backend.vercel.app/

Steps to Reproduce

1. create vercel.json
2. write

{
  "version": 2,
  "builds": [
    {
      "src": "dist/main.js",
      "use": "@vercel/node"
    }
  ],
  "routes": [
    {
      "src": "/(.*)",
      "dest": "dist/main.js"
    }
  ]
}

3. vercel login
4. npm run build
5. vercel --prod

[zshnb]

does anyone can help me?