Fix 'Git Remote Origin Already Exists' When Updating Remote URL - Cloudflare 521 Error: Port 443 Blocked Fixes-DNS Probe Finished NXDOMAIN: Troubleshooting Checklist

Prepare
Execute
Validate
Document
Operational follow-up
- Record the exact option, command, or setting that changed the result.
- Keep a rollback note if the workflow affects shared files or team settings.