A company accepts payment requests 24x7.

Middleware should coordinate request delivery and payment processing, and Payment System should process a payment request only once. This solution ensures that each payment request is delivered to the Payment System in a reliable and consistent manner,and avoids duplicate or conflicting updates to the same Payment Request record. Middleware can act as a mediator between the Data Entry Point and the Payment System, and implement logic to handle errors, retries, and acknowledgments. Payment System can usethe globally unique identifier to check if a payment request has already been processed, and avoid processing it again. References: Certification - Integration Architect- Trailhead, [Integration Patterns and Practices]