This roundtable explores how providers can safeguard their Provider Transaction Access Number (PTAN) amid evolving Medicare enrollment regulations. Participants will examine the most common—and often overlooked—compliance failures that lead to PTAN deactivation, including failure to report changes of ownership, practice location, or adverse legal actions within required timelines. The session highlights how Medicare Administrative Contractors (MACs) evaluate enrollment files, what triggers retroactive deactivation, and how providers can build internal processes to avoid interruptions in billing privileges. Real case examples illustrate how providers lost months of revenue because they were unaware their PTAN had been deactivated until claims began denying. The discussion concludes with practical strategies for monitoring enrollment status, documenting changes, and communicating with MACs to maintain uninterrupted billing privileges.