v0 Preview Terminates Dev Server + Can't Create New Chat or Support Case

I’m experiencing multiple platform-level issues with my v0 project that I cannot resolve through normal troubleshooting.

Primary Issue: Preview Sandbox Terminating Dev Server

My v0 project Preview is stuck on the black Vercel loading screen. The homepage sometimes appears briefly, then disappears and the loading spinner continues indefinitely.

The app previously worked normally. Project files remain intact and my Neon database still contains the published content. The managed v0 Preview environment repeatedly terminates or restarts the Next.js dev server, leaving no process listening on port 3000.

I checked the runtime logs and manually started the server through the v0 agent. Next.js reached “Ready” and the Neon connection was successfully queried, confirming the code and database are working correctly. The process was then terminated by the Preview environment anyway.

The issue began after restoring the project’s DATABASE_URL, although the database connection itself is valid.

Attempted fixes:

  • Triggering file updates
  • Reloading v0
  • Reopening the Preview
  • Restarting preview generation
  • Hard refresh, incognito window, different browsers

Secondary Issue: Cannot Create New Chat

Attempted to create a new chat to get a fresh sandbox, but the new chat button is stuck on a loading spinner.

Tertiary Issue: Support Case Form Bug

When attempting to submit a support case, the form shows my account as “V0 Free” despite being on the Business Plan ($100/user/mo). This prevents me from submitting a case. Screenshot attached showing my plan and the case form discrepancy.

Project Details:

  • Project ID: prj_MqrAHXf0RhACX0udVuPqOWGYWTLM
  • Team slug: strategy-5152s-projects

Happy to provide additional account details via DM to any Vercel staff investigating.

Hi Simon,

I’d split this into “app boot” and “v0 workspace/account UI” because they may not have the same cause.

For the app side, since the issue started after restoring DATABASE_URL, I’d first make sure the dev server is not exiting because something loads the database at startup and then throws after the initial “Ready” line. In the v0 terminal, I’d check the dev script and run it as directly as possible:

cat package.json
npm run dev -- --hostname 0.0.0.0 --port 3000

Then watch the logs after the Neon query succeeds. If there is any error after “Ready”, even a delayed one from a Server Component, route handler, Prisma/Drizzle init, or middleware, that could explain the preview going back to the spinner.

I’d also double-check the restored DATABASE_URL for accidental wrapping quotes, trailing whitespace/newlines, or a value from a different Neon branch/project. Don’t paste the actual URL publicly, but it’s worth comparing the first part/host against the Neon branch you expect.

The separate red flag is that creating a new chat also spins forever and the support form shows the wrong plan. That part does not sound like app code. For that, I’d avoid posting more project/team/account IDs publicly and keep the escalation to non-secret evidence: chat URL, project ID already shared, exact UTC timestamps, screenshot of the plan mismatch, and the preview/runtime log lines showing the dev server being terminated after it reaches Ready.

If GitHub is connected, I’d also make sure the latest files are pushed or exported before trying any destructive recovery steps like deleting/recreating chats.

I would try the same commit outside the v0 preview and check that DATABASE_URL is enabled for development