I think the issues is likely the spine not having muscles enabled.
When the spine is running without the muscles instead it add joint torques generators in the lumbar joints, these are possibly not strong enough.
Since you have no muscles in the spine i assume that you are not interested in spinal forces, so you could simply add an AnyReacForce to all the lumbar joints, then I think the overloading of psoas will go away.
Really really thanks. Now I know the reason why...
So I changed the model to full body. but I don't have arm marker.
Is there a way to remove only arm in the full body model??
I would switch back to the lower extremity model and just enable the spine muscles (or add the reactions as i suggested)
If you go to Labspecific.any file you will find the file BodyModelConfig.any being included. In this file the different BM is set and you can enable the trunk muscles alone.