AI Perception - Sight

Hello, have a question about AI perception, specifically sight. In my project, there is an enemy, an ally and the player. The enemy and ally spawn next to each out, the player spawns out of sight. How my behavior tree and perception are working is, when the AI controller (both enemy and ally) sees an actor that is an enemy, it makes it the “targe actor” and moves to it, and attacks. All of that is working fine. This works off of the sight perception. The issue i’m having is; as the player, when I walk into the enemies sight, while it is fighting the ally, it perceives me, but because it already has a valid target (the ally), it ignores me, which is perfect - I want it to focus first on its current target. But what happens is, it kills the ally, and the target actor gets cleared, which is what I want, but it won’t register the player (even if I am standing right in front of it) as a new target.
I think what is happening is because it already perceived it via sight and had another target, it now is ignoring it.
Testing with the debugger, it apprears that the AI sight only triggers once, as I continue to move in the AI’s sight cone, it only triggers the inital perceived location. This works different from hearing, which continues to perceive each step.
I guess what I’m looking for is a way to force to AI controlled to redue sight perception, once it no longer as a valid target, to re-identify the player.
Thank you for any help!