Wrong Purchasing Organization in freight Order

Hi Experts,

I have created a freight order in TM 9.1 as a result of optimizer planning. However the purchasing organization appearing in the freight order is not in line with what is defined in freight order type configuration. I tried changing the same but during the document saving, it is again moving back to wrong purchasing organization. Due to this the charge calculation is also not happening as freight agreement has different purchasing organization. Any idea on how to resolve the issue?

Thanks in advance for your help

Regards

Sandeep Patil