Inbound delivery - Error when creating document flow for delivery #########

Hello all:

When attempting to PGI an inbound delivery (via VL06I - For Goods receipt - select inbound delivery - click Post Goods Receipt) I received error messgae VL 659:

Diagnosis

As the system was recording the document flow for the goods movement, it determined that the subsequent document number is either blank or identical to the number of the preceding document.

System response

In order to avoid inconsistencies, the goods movement posting was cancelled.

All WMS transfer orders tied to this inbound delivery are complete. This hasn't happened with any other delivery. Any suggestions as to what I can do?

Thanks,

Bill