My PHP-based e-commerce back-office is already wired to the Mercado Libre API, yet the moment the access token expires the whole link goes down and I start getting “failed to connect to Mercado Libre API”. I have not attempted any troubleshooting so far. What I need you to do: • Review the current OAuth flow in the existing PHP codebase and update it so the token refreshes automatically before it expires. • Make sure the restored connection allows my local MySQL database to stay perfectly in sync with listings, inventory and orders on Mercado Libre. • Test the fix end-to-end so that product uploads, status updates and order retrieval all complete without errors. Acceptance will be based on: 1. Successful authenticated calls to Mercado Libre API from my server for at least 24 hours straight. 2. A manual trigger or cron job that renews the token without human intervention. 3. Database entries that mirror the platform data after a full sync run. The project is fully contained: the server, credentials and current PHP files are ready for you in a private repo. If you’re comfortable with PHP 8, cURL/Guzzle, and MercadoLibre’s REST endpoints, you should find this straightforward.