Creatures flee from battle

OK so have noticed something with my intelligent minions.

I place a rally flag near enemies in order for my fighting force to attack.

Please note that majority of creatures are at at least level 4, a few under and a few higher.

Now all creatures and beasts come to rally flag and attack enemy let's say there's about 4 enemit's, mixed level but highest been 4.

My creatures will attack for a bit but then will flee for a few tiles then run back and attack again.

I can't understand why they would flee when A) there are a total of more of my creatures than enemies and B) my creatures are of the same or higher level than the enemy and even my creatures that have a lower level should feel better knowing that the higher level creatures are there to back them up.

Could this be looked at.

P.S sorry Lee "Noontide" ☺