[BUG]Magic-link email login redirects to onboarding for existing Max subscriber — fifth public report of same backend auth-routing failure

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Magic-link email login on claude.ai consistently redirects to the onboarding flow ("Let's create your account") for an active Claude Max subscriber, instead of authenticating into the existing account. The backend appears to fail to map the verified email to the existing Max account record and drops the session into the new-user onboarding flow without surfacing any error.

This is the same auth-routing pattern documented in #36797, #39788, #51002, and #57164. At least the fifth paying Max customer publicly affected by what appears to be the same underlying backend identity-mapping failure.

Account Context

• Account email: admin@fundacionnuevaconsciencia.com
• Subscription: Claude Max — active and currently being billed
• Functional session: Claude mobile app, still authenticated with full Max access (confirms account exists and subscription is active)
• Broken sessions: all desktop and web browser login attempts; Claude Desktop app

Actual Behavior

• Magic-link handshake completes successfully (email verified by the backend)
• Backend fails to recognize the verified email as belonging to the existing Max account
• Session is dropped into the new-user onboarding flow as if the user had no account
• No error message surfaced — silent auth-routing failure

I have deliberately NOT clicked "Create account" on the onboarding page to avoid creating a duplicate account under a different auth provider, as documented in #51002.

What Should Happen?

Clicking the magic link with a verified email that maps to an existing Max account should authenticate the user into that account and route them to the dashboard on claude.ai web and Claude Desktop, exactly as it currently does on the Claude mobile app.

Error Messages/Logs

Steps to Reproduce

1. Open claude.ai in any desktop browser (Chrome, Firefox, Edge).
2. Enter admin@fundacionnuevaconsciencia.com on the login page.
3. Open the magic link received at that email address.
4. Browser is redirected to claude.ai/onboarding?returnTo=/magic-link with "Let's create your account" and the email shown as verified.
5. No dashboard appears, no error message, no path back to the existing account.

Reproduced on:

• Multiple browsers (Chrome, Firefox, Edge)
• Incognito / private windows
• Multiple physical machines
• No VPN
• After clearing cookies, cache, and deleting all API keys from console.anthropic.com

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

N/A — claude.ai web/desktop magic-link auth bug, not a

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

Important context: This is not strictly a Claude Code CLI bug.

This issue is filed on the claude-code repo per the precedent established in #47290 and #51002, where backend / billing / auth issues required engineering escalation because Fin AI Support could not resolve them. The auth failure described above affects claude.ai web and Claude Desktop, though Claude Code OAuth login is also affected since it uses the same backend identity-mapping logic (see #19160, #31124, #39788). The Claude Code-specific fields above (model, version, terminal) were marked N/A for that reason.

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Related issues — same backend auth-routing failure pattern:

• #36797 (Mar 2026) — Authentication redirect loops to onboarding for existing account with active subscription
• #39788 (Mar 2026) — OAuth login redirects to account creation instead of authenticating existing Max subscription
• #51002 (Apr 2026) — Desktop app connector flow creates duplicate account under same email, locks paid Max subscriber
• #57164 (May 2026) — Google OAuth login redirects to onboarding for existing Max subscriber

This is at least the fifth paying Max customer publicly affected by what appears to be the same underlying backend identity-mapping failure.

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Support path attempted (Fin AI dead-end loop):

1. Fin AI Agent on support.claude.com — Conversation ID 215474292054390. Did not escalate; recommended self-service troubleshooting that does not apply (the bug is server-side).
2. Email to support@anthropic.com — Conversation ID 215474314952347. Only Fin auto-reply received.
3. Explicit follow-up email requesting human escalation, with written request not to close the conversation by bot. No response.

72+ hours have elapsed since the email to support@anthropic.com with no human responder, matching the timeline reported by other affected Max subscribers in the issues linked above.

Per the public "How to get support" article, Fin AI should hand off to human Product Support when a Pro or Max subscriber explicitly requests escalation. In my conversation, it did not.

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Verification offer:

I can privately provide to official support channels (not in this public issue):

• Account email confirmation
• Paid invoice PDFs (recent months)
• Card last-4 digits
• Account creation timestamp
• Mobile app screenshots showing active Max plan
• Browser console logs and screenshots of the redirect flow

Happy to verify identity, payment method, and account ownership via any channel that is not a dead-end bot loop.

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Requested action:

1. Engineer-side fix of the auth-routing logic so magic-link logins for admin@fundacionnuevaconsciencia.com resolve to the existing Max account on desktop and web.
2. Confirmation that no duplicate account has been silently created under this email.
3. Process fix: Fin AI should hand off to a human Product Support agent when a Pro or Max subscriber explicitly requests escalation, as described in the public "How to get support" article.

/cc area:auth