The reason he was dominated by Hall was purely physical. Hall was stronger and faster than him, it's really that simple. He couldn't take it past him, he couldn't beat him 1v1.
This is not the first time we've seen this happen to Lamine because, frankly, he's not particularly fast and he's got a tiny frame. But this is where he needs IMO to offer something different; just waiting on the wide right so he can pretend to dribble his dominant fullback and then pass back is too static. I'd like to see him go elsewhere and make runs in behind or get involved deeper.
Also, his workrate without the ball was SHIT on many occasions.