Even with correct serials, Revit 2019 is notorious for failing to activate. Below are the fixes for the most frequent error codes.
Activating Revit 2019 has changed significantly in recent years. Autodesk has moved toward a "Named User" model, phasing out serial numbers for new subscriptions. However, depending on your license type, you will fall into one of two scenarios: autodesk revit 2019 installation and activation
Summary
If you purchased your subscription recently or migrated to the new model: Even with correct serials, Revit 2019 is notorious
Single-user activation (typical):
Network license activation:
