I'm playing as Empire. Sometimes when I go up against the vampires they come with like 3-4 stacks of reinforcements. The problem is even though I beat them badly, it will show them having 0 units on the field like "0/2487" and the game wont end.

I see some units of their reinforcements stuck on the outside of the map but they wont come in so I cant actually end the game without destroying my army completely, even though I won. Even when I wait it out its only a draw.

Any suggestions?