[BUG]Annual Pro subscriber cannot upgrade to Max — "billing address changed" error hard-blocks the upgrade (claude.ai web)

Preflight Checklist

• [ ] I have searched existing issues and this hasn't been reported yet
• [ ] 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?

I'm an annual Pro subscriber and I cannot upgrade to Max. The upgrade screen on claude.ai is hard-blocked by an error saying my billing address has changed since my last invoice. I've changed the billing address several times (to the last invoice address and to new ones) and also changed the payment card. The error persists every single time. This is not a data problem on my side. It matches issue #58402.

What Should Happen?

The upgrade from annual Pro to Max should complete. If the billing address truly needs updating, it should be editable inline in the upgrade flow. The "contact Support" message should route to a human who can unblock it manually within a reasonable timeframe, not to a bot that doesn't escalate.

Error Messages/Logs

ES: "Su dirección de facturación ha cambiado desde su última factura. Para actualizar a Max, contacte a Soporte para obtener ayuda."
EN: "Your billing address has changed since your last invoice. To upgrade to Max, contact Support for help."

Steps to Reproduce

1. Log in to claude.ai as an annual Pro subscriber.
2. Go to Settings > Billing.
3. Click "Upgrade to Max".
4. The error appears and blocks the upgrade.
5. Changing the billing address (any value) and the payment card does not fix it.

Claude Model

Other

Is this a regression?

No, this never worked

Last Working Version

Unknown

Claude Code Version

N/A — issue is on claude.ai web, not Claude Code CLI.

Platform

Other

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

This is a duplicate of #58402, filed only because I couldn't add a comment there. I've been trying to upgrade for two months through support tickets and the chat bot, which doesn't escalate to a human. I want to pay for Max but can't get past this screen.