"Database operation failed" error with Vercel KV in Next.js app

Hello Vercel Community,

I'm encountering a persistent issue with my Next.js application using Vercel KV for user registration. Despite following the documentation and implementing several debugging steps, I'm still unable to resolve this problem.

Issue: When attempting to register a new user, I receive a "Database operation failed" error. The client-side error message is:

Steps taken:

Verified all required environment variables are set (KV_URL, KV_REST_API, KV_REST_API_TOKEN, KV_REST_API_READ_ONLY_TOKEN).
Implemented detailed server-side logging in the registration API route.
Created a debug endpoint to test Vercel KV connection.
Checked Vercel logs for any error messages during registration attempts.

Relevant code:

Registration API route (app/api/auth/register/route.ts):

1import { NextResponse } from "next/server"2import { hash } from "bcryptjs"3import { kv } from "@vercel/kv"45export async function POST(request: Request) {6  console.log("Registration route called")7  try {8    const body = await request.json()9    console.log("Request body:", JSON.stringify(body))1011    const { name, company, email, password } = body1213    if (!name || !company || !email || !password) {14      console.log("Missing required fields")15      return NextResponse.json({ message: "All fields are required" }, { status: 400 })16    }1718    try {19      console.log("Checking if user already exists")20      const existingUser = await kv.get(`user:${email}`)21      console.log("Existing user check result:", existingUser)2223      if (existingUser) {24        console.log("Email already exists")25        return NextResponse.json({ message: "Email already registered" }, { status: 400 })26      }2728      console.log("Hashing password")29      const hashedPassword = await hash(password, 10)3031      const newUser = {32        name,33        company,34        email,35        password: hashedPassword,36      }3738      console.log("Attempting to save new user")39      await kv.set(`user:${email}`, JSON.stringify(newUser))4041      console.log("User registered successfully:", JSON.stringify(newUser))42      return NextResponse.json({ message: "User registered successfully" }, { status: 201 })43    } catch (dbError) {44      console.error("Database operation error:", dbError)45      return NextResponse.json({ 46        message: "Database operation failed", 47        error: dbError.toString(),48        stack: dbError.stack49      }, { status: 500 })50    }51  } catch (error) {52    console.error("Unhandled registration error:", error)53    return NextResponse.json({ 54      message: "Internal server error", 55      error: error.toString(),56      stack: error.stack57    }, { status: 500 })58  }59}