We have a customer that has recently upgraded to Sage 300 2021.  They encountered this problem entering a sales shipment and trying to apply Lot Numbers to it.  Although there was sufficient quantity available if they looked in either location details or on the quantity on hand report, the quantity wasnt available to select within the Shipment Entry Lot Number Allocation Screen.  Running a data integrity check and for that item and a number of others it reports the error:

E: ICXLOT.QTYORDED for lot number {Lot Number}, item {ItemNo} at location {Location} does not match the sum of the lot quantities on order

If I run the DIC with fix, that resolves as it updates the quantity shippable to be correct.  However, the issue reoccurs when any item that has lot numbers has been shipped since the last DIC with fix has been run.

Has anyone come across this?

Thanks in advance