Offset of surface failing? any possible solution?

I have a face that Salome is failing to offset, the face, I have created in another CAD software and there I can offset it without issues. I tried the offset surface and also the thickening tool in geom and didn’t find any ‘similar’ tool in shaper. if the developers could help me to solve this or confirm me that salome is not capable of doing this I will be grateful.
here is the step file:
surf.step (16,4 KB)

and an image of the surface with its offset in the other software (also the step with the two surfaces)

twoSurf.step (83,4 KB)

best regards,