[BUG] Gmail Connector Re-authentication in Desktop App Breaks Login for Existing Paid Account. All Surfaces Route to Onboarding

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?

Disconnecting and reconnecting the Gmail connector in the Claude desktop app broke authentication for my existing, active, paid Claude account. Every login surface now routes to the claude.ai/onboarding “Let’s create your account” page, with my email shown as verified, instead of authenticating into the existing account. No error is surfaced and there is no path back to the account.
This is the same backend identity-mapping failure documented in #36797, #39788, #51002, #57164, #60022, and #71262. Mine is the connector-triggered variant, closest to #51002.

Environment
• Claude Desktop, macOS
• Claude mobile app, iOS
• Chrome, plus additional browsers tested
• Claude Code CLI fields: N/A. Filed on this repo per the precedent in #51002 and #57164, where backend auth and billing issues required engineering escalation because Fin AI Support could not resolve them.
Evidence the account exists and is billed
Anthropic charged my card on the same day the issue began. Receipt and invoice numbers, card last four, and account creation details available privately via official support channels.
Ruled Out
• Mobile app reproduces the issue, sharing none of the desktop browser’s cache, cookies, VPN, or extensions
• Chrome Incognito (no cookies, no extensions): reproduces
• VPN disabled: reproduces
• Site data cleared for claude.ai, claude.com, anthropic.com: reproduces
• Individual plan, so SSO and provisioned organizational seats are not applicable
Not Done, Deliberately
I have not clicked “Create account.” Per #51002, doing so creates a duplicate account under the same email with a different auth provider and locks the user out of the original paid account.
Support Path So Far

What Should Happen?

Re-authenticating a connector should not affect Claude account session identity. Any subsequent login with a verified email that maps to an existing paid account should resolve to that account, not fall through to the new-user onboarding flow.
Actual Behavior
All login surfaces (Claude Desktop, Chrome, additional browsers, Claude mobile app) route to the onboarding / account creation page. The account exists and is actively billed.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce

1. Have an existing, active, paid Claude account (individual plan).
2. Be signed in on the Claude desktop app.
3. Settings, Connectors, disconnect the Gmail connector.
4. Reconnect Gmail, authenticating with the same Google account tied to the Claude account.
5. Observe: subsequent logins on desktop, web, and mobile all route to claude.ai/onboarding and display “Let’s create your account” with the email shown as verified.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

na

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_