Do not skip this. The simplest fix is often the correct one.

What is the (is it a "prototype" or "engineer" unit)? What is the exact error code appearing on your screen?

The tool recognizes the iPhone 9 series but lacks the specific "3d101ap" instruction set.

Q: What does the "loader for iPhone 9 3D101AP not found" error mean? A: The error indicates that the loader, a critical component of the iPhone's operating system, was not found.