Pz III L can’t pen KV1 at touching range

I ran directly behind a kv1 with a slow turret and shot it 15 times on the big fat box and it did nothing. I’m using the second ammo with higher pen.

Just don’t understand how to pen a kv1. I watched the video online saying you shoot the turret cheek with Pz III but at 0 meters still didn’t work…