Fix checkout Issue

Seeking an experienced UK or US-based developer to diagnose and resolve checkout issues on https://www.bitrixa.com/. The task involves investigating payment flow, reproducing errors, reviewing logs, validating integrations (payment gateways, SSL, API endpoints), and implementing robust fixes. Deliverables: bug report with root cause, applied corrections, and verification of successful transactions across devices and browsers. Strong e-commerce, security, and debugging expertise required to ensure reliable, secure checkout operations.