We discovered a situation where we have multiple SKUs with negative inventory quantity when they are lot controlled.  This appears to have happened from a physical inventory count and adjustment.  

Background - we had some lot controlled inventory get stranded when we deleted an invoice in progress in December.  First time we ever had this happen.  Ran an IM rebuild utility to free up the stranded inventory.  Made sure there were no open invoices, production entries, or document where inventory had been assigned.  The stranded inventory was released and we were able to use on a new invoice.

However, we noticed a new cost tier for the same lot and quantity was duplicated in the Cost Detail tab.  BUT the overall inventory on hand was correct on the Main tab.  

During the physical count - the duplicate lot and quantity appeared as on hand in the count sheet but again overall qty did not include the duplicate inventory.  The duplicate was adjusted to 0 on the count sheet transaction to remove and then the lot quantity went negative.  We noticed this happened for other SKUs that were not part of the original stranded inventory issue.

I was under the impression you could not take a lot controlled item into a negative quantity.

Any idea on what caused this to occur?

How to correct?

Thanks.