Problem AI detecting my physics based Pawn

I got a problem using the AI Perception system trying to sense my character (that is a pawn based on physic). So I have my AI Controller with AI Preception (Sight) and I’m using OnTargetPerceptionUpdate to check when the AI character detect my Pawn to be able to follow it. I use CastToPawn to associate my variable ‘PlayerDetected’ to my blackboard variable for the BehaviourTree but here I get the issue. I see that when I move near the AI enemy it will not detect me, but if it get near the point of my spawn it detect something there and keep moving toward that point (as if my pawn is never moved from it’s original point of spawn and the AI detect something in that point). Any Idea to how to manage this issue? What can be the cause?