It has been brought to my attention that there is a problem with troops showing up on the map page, but when viewing the specific territory they are no longer shown. The problem appears to be due to some reassignment after moving into enemy territory but prior to the attack. If the attacker is forced to retreat, during retreat troops and generals are sent back to their previous location. At that point, the system is looking for which general these troops are assigned to and although they are assigned to a general, that general doesn't exist in their location.
So... basically, the system is allowing you to reassign troops to another general while in enemy troops are present, which should not be allowed. Until the system is corrected to block such situations from happening, please do not reassign any troops to generals that are from different territories when you go in to battle.