No Output Directory named "public" found for next JS

Hello - After deploying a two-part project on vercel, the following error appears in deployment log of the frontend part: “Error: No Output Directory named “public” found after the Build completed. Configure the Output Directory in your Project Settings. Alternatively, configure vercel.json#outputDirectory.”
The ‘Root Directory’ is set to the frontend directory of the project.
This is a monorepo project with two projects on vercel.
The backend project deploys successfully.
What other factors could cause this issue.
I appreciate any helpful responses. And please talk down when describing technical steps and how-tos.

The frontend is nextJS and the ‘Framework Preset’ is set accordingly.

The env variable ‘NEXT_PUBLIC_API_URL’ is pointing to the public domain of the backend project, which is deployed successfully. Below is the contents of vercel.json.
{
“version”: 2,
“builds”: [
{
“src”: “src/main.ts”,
“use”: “@vercel/node”
}
],
“rewrites”: [
{
“source”: “/api/(.*)”,
“destination”: “/src/main.ts”
}
]
}

This should work if you remove the builds config from your vercel.json

Manually specifying the builds overrides the Next preset and leaves you in an intermediate state where you would need to configure many more things (including how to create the public directory)