2063220 - Port of Loading is changing when Stages are added outside of Port to Port - SAP TM

The shipment is going from Pick up Location to Delivery Location Via Port of Loading and Port of Discharge
But the total route is Loading a consol container in the Pick up location Deliver the container to intermediate to rail to Port of Loading to Port of Discharge Delivery container to new location

So to add Pick up Location - Intermediate , we are going to stages tab in Freight Booking and when we are selecting the stage 10 and clicking on intermediate stop,
system is showing an error message "Split is not permitted for stage Oceanfreight Ex XX to XX - Stage; only for main carriage"
So if then we are trying to select the stage 20 and click on Intermediate stop ,
system is adding one more stage and then we are maintaining accordingly Stage 10: Pick up location - Intermediate Stage 20: Intermediate - Port of Loading Stage 30: Port of Loading - Port of Discharge Stage 40: Port of Discharge - new location

But now if I go back to Location tab the Port of Loading is changed which business expects to be maintained as Port of Loading.

TM 9.0

TM, Transportation Management, FB, freight booking, Forwarding order, POL, POD, incorrect, bad, moving, moved, change, set, , KBA , TM-FRM-FRB , Freight Booking , Problem