Full AWS Practitioner Certification Question

A financial analytics firm runs two decoupled services. One service generates financial transaction payloads and sends them hourly for processing. The processing service may take up to 48 hours to complete handling each transaction. To ensure resilience, failed transactions must be captured without disrupting the processing of others. The firm needs a solution that requires minimal infrastructure management while remaining highly scalable and fault tolerant. Which solution best addresses these requirements in the most operationally efficient way?