Workers Stuck At Entrance

So, this looks like a normal screenshot, but the workers at the entrance were just doing nothing. They would just be frozen but then sometimes randomly start moving again, and then they would get frozen again. I had gather on and attack off for ALL of my ants. It's also worth noting that the workers who weren't at the entrance SEEMED to be acting normal (they could have been fighting or frozen, but I can't see them clearly).