CoreTwin-Autonomous Fault Management is an AI-powered autonomous operations solution that enables Communication Service Providers (CSPs) to rapidly identify, isolate, and resolve root faults across increasingly complex cloud-native core networks. As networks evolve to span cloud infrastructure, SDN environments, IP transport, and core applications, traditional fault management approaches struggle to cope with the scale and volume of alarms generated by a single failure. CoreTwin-Autonomous Fault Management addresses this challenge through a dynamic, real-time Digital Twin of the cloud core environment, providing end-to-end visibility across application, infrastructure, and IP-core domains while automating Root Fault Origin (RFO) identification within minutes. At the heart of the innovation is a multi-domain, multi-layer Digital Twin that continuously correlates topology, alarms, KPIs, and service dependencies across cloud, CS Core, PS Core, IMS, and IP-Core environments. Combining AI-driven analytics, confidence-based root cause identification, intelligent noise reduction, and an LLM-powered operational assistant, the solution enables operations teams to interact with complex network environments using natural language while receiving highly accurate fault insights and remediation recommendations. This creates a unified operational view that replaces fragmented troubleshooting processes and dramatically accelerates fault isolation. The project advances beyond conventional monitoring and fault management by introducing predictive intelligence and closed-loop automation aligned with TM Forum's Autonomous Operations Framework. Through the integration of historical performance analytics, fault correlation, automated ticket enrichment, and workflow orchestration, CoreTwin-Autonomous Fault Management not only identifies the true source of a fault but also initiates targeted operational actions. The Digital Twin becomes a continuously evolving AI knowledge layer that supports simulations, predictive analysis, and proactive service assurance, helping CSPs move toward Level 4 and Level 5 autonomous network operations with minimal human intervention. The business value is significant. By reducing root cause identification time from hours to under 10 minutes, cutting Mean Time to Resolution (MTTR) by up to 50%, and reducing alarm noise by more than 80%, CoreTwin-RFO enables CSPs to improve network availability, protect revenue-generating services, and enhance customer experience. The solution eliminates costly cross-team diagnostic handoffs, streamlines ITSM processes, and strengthens operational resilience across multi-vendor environments. Ultimately, CoreTwin-Autonomous Fault Management transforms network operations from reactive firefighting into a predictive, automated, and business-centric model that delivers measurable efficiency gains, improved service reliability, and a faster path to autonomous network operations.