Unlock Tool Platform Enhancements

I run an online credit-based platform that lets Xiaomi owners remove Google-ID locks through an external unlocking API. The core stack is PHP with a browser-based UI, plus my own user, reseller, and admin panels. Right now the integration is shaky: the API drops its connection too often, interrupting unlock requests.

Here is what I need fixed or built:

• API layer – stabilise the PHP code so it keeps a reliable session with the supplier’s endpoint, handles retries, and surfaces clear error messages when the service is down.
• User panel – allow customers to purchase credits, track every unlock they perform, and manage their basic account details.
• Reseller panel – let resellers top up credits for their sub-users, view their sales history, and handle their own profile settings.
• Admin panel – give me full visibility and control over users, resellers, credit flows, and logs, plus the ability to update API keys without downtime.

If you are comfortable across PHP, RESTful API work, and lightweight responsive UI, I’d like you to audit the current codebase, explain your approach, and deliver tested, production-ready updates.