Entries in BBP_DOCUMENT_TAB, doc_type = IM


I have a shopping cart that generated a purchase order.

Now, the user is trying to do "Confirm Goods Receipt". But when he clicks on the order, he receives the message BBP_CF044 "Error blocking purchase order in backend. Inform system administration".

In the table BBP_DOCUMENT_TAB I could see three entries (one for each item in the PO). And the DOC_TYPE = IM. What does it mean?

The report CLEAN_REQREQ_UP runs every 20 minutes.

What can I do?