CRM Service order Replication

HI,

We created service order and entered the spares ,as per the business process it have to create the PR for particular spare but for some line items it not showing in the PR . In service order showing error like Error in coping order clint 400.

I checked in the Q it is showing the error massage for R3AUORDER_XXXXX  error sysfail Purchase order is not created  for 40 items.

With Regards,

Prakesh.