Blanket PO information not populated on imported requisitions

Most of our requisitions are created directly by users from a catalogue in iProc. However we do import some requisitions via the standard REQIMPORT process. The DOCUMENT_TYPE_CODE,  BLANKET_PO_HEADER_ID and BLANKET_PO_LINE_NUM do not get populated for the imported requisitions although it does for user created requisitions. I'm not sure what needs to happen to make this work, as it prevents PO's from automatically creating.

We do not use inventory or MRP, nor do we use an ASL.

Can anyone help?

Thanks,

Rachel