Onhand Inventory, Available to Reserve showing negative quantity

 We have an item that is showing onhand inventory of 10,000 units, a positive Available to Transact and yet the Available to Reserve is negative 7,000 units.  Would have thought that the once the Available to Reserve hit '0' then addtional reservations would not be allowed.  Looking for an explanation on this issue.

Okay, so the more I thought about it there was a sequence of events which led to the negative ATR quantity.  Batches were released from the Planners workbench in May and not executed, effectively building a backlog of reservations.  Then in recent days a couple of the lots covering the reservations expired and created the negative ATR.  The solution was to retest the expired lots and extend the expiration dates, which corrected the negative ATR.  Hope this helps anyone who encounters this issue in the future.