how to define unmatched ports in HFSS and CST?

Hi,

I have designed a waveguide T-junction in both HFSS and CST, and I wanna have 2of 3 port be unmatched (with specified resistance and reactance). I couldn't find any capability in CST in defining such port but in HFSS with lumped port I could define the impedance but the result is not true. Is there any correct way to do it in HFSS and CST?

Best regards

Amir