Next.js Next auth API Route TypeScript Compilation Error: 'Type error: Route does not match the required types of a Next.js Route.'

Question

I'm encountering an issue while working on a Next.js project. When attempting to create an optimized production build, the TypeScript compilation fails with the following error:

Compiler edge-server unexpectedly exited with code: null and signal: SIGTERM
✓ Compiled successfully
Linting and checking validity of types ..Failed to compile.

app/api/auth/[...nextauth]/route.js
Type error: Route "app/api/auth/[...nextauth]/route.js" does not match the required types of a Next.js Route.
"default" is not a valid Route export field.
Linting and checking validity of types ... (additional details, if any)

This is the full code snippet

// app/api/auth/[...nextauth]/route.js

import NextAuth from "next-auth";
import CredentialsProvider from "next-auth/providers/credentials";
import client from "../../../../lib/sanityConfig";

export const authOptions = {
  providers: [
    CredentialsProvider({
      name: "Credentials",
      async authorize(credentials, req) {
        const { username, password } = credentials;
        const sanityQuery = `*[ _type == "admin" && username == $username && !(_id in path('drafts.**'))] {
          username,
          password,_id
        }[0]`;
        const user = await client.fetch(sanityQuery, { username });

        if (!user) {
          throw new Error("admin Doesnt Exist");
        }

        const match = password == user.password;

        if (!match) {
          throw new Error("Invalid credentials");
        }

        return user;
      },
    }),
  ],
  pages: {
    signIn: "/login",
  },
  secret: process.env.NEXTAUTH_SECRET,
};

const handler = NextAuth(authOptions);
export { handler as GET, handler as POST };

I'm seeking help in understanding the root cause of this TypeScript compilation error and any possible solutions or suggestions to resolve it. Has anyone encountered a similar issue with Next.js API routes and TypeScript, and how was it resolved?

What did you try: I attempted to resolve the issue by:

• Adjusting the export structure in my app/api/auth/[...nextauth]/route.js file.
• Verifying the TypeScript configuration in my tsconfig.json file.
• Searching on Google and ChatGPT for solutions, but I couldn't find a resolution.