ASME NC Nuclear expansion problem

I designed my piping system in Bentley AutoPIPE Nuclear, and i have to do my analysis using the ASME NC Nuclear code.

I am interested in forces/moments and mainly in stress, for sustain and expansion (gravity and thermal analysis)

The stress values in the sustain analysis are very accurate, about 30 MPa and the allowable is 121MPa as i expected.

The problem is that for thermal analysis, i get no values. The force/moment/stress in every node is 0 for thermal Analysis with ASME NC.  What should i do to fix that?

To check if i made a mistake, i changed the code to ASME NB and there i get values also for Thermal/Expansion, so i assume the problem is in the ASME NC equations in AutoPIPE.

Any advice for how to fix it?