NPCs sometimes can't be hit

Game mode: Singleplayer
Problem:Bug
Region: US Est


When trying to attack enemy npcs, I often encounter a bug where my attacks go right through them, and their attacks go right through me. Neither of us can damage or stagger each other. It always happens with archers when they are standing underneath awnings/ tents in npc camps. I have to get them to chase me so they move out from the buildings and I can actually hit them. It also happens sometimes with the purge where npcs are hitting my buildings and my attacks just go right through them. Please fix your game!