So... you slash a bush, and the undercombo is a bush that you cannot cut. You activate the armos, and under it is an armos that will not move...
Well, all I can suggest is check the undercombos. Also, if there are any layers on the screen, make sure there are no undercombos or flags on the screen you're using. I'm not entirely familiar with the newest 2.5 build so I don't know if I'm much help here, but thats my .02.