Error when trying to inset angled circular face

[Spyro-JoKeR]

I can't figure out how to inset this face (see images) by ~1mm. I tried using Offset Face but get this error:

Error: The operation could not create a valid result.
Try adjusting the values or changing the inputs.

The model was an imported mesh but it has been converted to a body and the face I'm trying to inset was created by cutting out a cylinder so its a clean surface. Anyone know why this won't work?

[TrippyLighting]

When offsetting a surface, Fusion needs to extend, or trim the triangular faces bordering that surface. That fails as there isn't a large enough surface to extend/trim.