Is anyone else having an issue with AI units walking through, sometimes fazing, through your formations like it's nothing. One battle I had a line of pikes up front, a secondary line of hoplites and a third line of hoplite mercenaries (keep in mind this is all within a siege, so think tight corridors and choke points). I had the AI blobbed in a narrow section of the town an they somehow walked through my formation like it wasn't even there, even without taking loses while disengaging... seeing that they were going to just walk through my formation of men I sent a reserve of men to form a fourth line to reinforce the line, yet again the AI shrugged it off and proceeded to walk through my line get behind my troops and slaughter me without taking too many loses while disengaging across the line. (just in case anybody asks, yes the troops were fully maintained and there was no unit that needed replenishment from a previous battle)

I was wondering if anyone knows of a way to combat this or if it is completely unavioidable/unbeatable