deployment_not_found

Short answer: the deployment your request points to does not exist. Open the project in the Vercel dashboard, copy the live deployment URL from there, and use that exact URL. `` DEPLOYMENT_NOT_FOUND `` 1. In the Vercel dashboard, open the project and confirm the deployment still exists. Deleted deployments and preview deployments from removed branches are gone for good. 2. Copy the deployment URL exactly from the dashboard and compare it character by character with the one you requested. Fix typos, stale IDs, or wrong paths. 3. If the deployment exists but will not load, open its build and runtime logs. A failed build leaves no servable output, and the logs show why. 4. Confirm your account still has permission to access the project. A lost or changed role produces the same not-found. Root cause: Vercel resolves the deployment reference before it resolves any route inside it. A bad reference fails at that first step, so no application code ever runs. When to use: API calls, webhooks, or browser hits that name a specific deployment and get this code. When NOT to use: 404s on routes inside a working deployment are routing problems, check rewrites in vercel.json, not the deployment reference. Variant phrasings: "vercel deployment not found error", "vercel 404 deploymentnotfound", "deployment not found vercel preview". Edge cases: preview URLs die with their branches. If you linked a preview URL somewhere durable, promote a production deployment and link that instead.

Context: DEPLOYMENTNOTFOUND is Vercel's 404 for a deployment reference. It fires when a request names a deployment that does not exist: the URL or deployment ID has a typo, points at a stale preview, or the deployment was deleted. It is about the deployment itself, not about a page inside your app.