Thank you for reaching out to us and we appreciate your patience.
These are my suggestions to hel you troubleshoot the issue:
- Did you verify whether your model is successfully imported into HFSS 3D layout? The way you do it is cross check all the nets.
- Did you run the simulation for the whole model instead of cutting it? Did you succeed in the simulation?
- Can you confirm whether you were able to modify the model before cutting?
Kindly check the above and let us know.
All the very best.