A user cannot Undo Shipment in Posted Sales Shipment document due to error: You cannot undo line XXX because inventory pick lines have already been posted.
This is according to the design.
System already have posted inventory pick.
You cannot do undo process until delete the posted inventory pick.
You can delete posted inventory pick if your location set as “Bin Mandatory” = no (this is not common scenario).
If you used location with “Bin Mandatory” = yes (in such case system play with an additional Warehouse Entry table), then no chance to deleted posted inventory pick and as result no chance to undo process. Undo process does not support undo Warehouse Entry.
