OCCGeometry GenerateMesh happens error

this is my code and happens some error
stp_fname = r’xx.stp’
hw_geo = OCCGeometry(stp_fname)
maxh = 5
minh = 1
grading = 0.5
mesh_size = meshsize.coarse
hw_mesh = hw_geo1. GenerateMesh (mp=mesh_size, maxh=maxh, minh=minh, grading=grading)

ERROR: Problem in Surface mesh generation
ERROR: Problem in Surface mesh generation
ERROR: Problem in Surface mesh generation
ERROR: Problem in Surface mesh generation
ERROR: Problem in Surface mesh generation
meshed area = 0.841148
maximal area = 0.544042
GIVING UP

but the code is block in GenerateMesh, How can i step out the GenerateMesh function and return to modify my model