It's the ADMIN_PASSWORD setting of this app's Vercel project.

1. Open your Vercel dashboard and pick this project.
2. Go to Settings → Environment Variables and find ADMIN_PASSWORD. Reveal it to see it, or edit it to set a new one.
3. If you changed it, redeploy (Deployments → ⋯ → Redeploy). New values only apply to new deployments.

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