Highlighting Enemies

I’m working on the prototype for my top-down, Hack n’ Slash Survival game. I’m fairly new to Blueprint scripting. After having some friends playtest the first build, it was suggested to implement some Diablo features. I am currently, I am having issues getting the highlighting feature to work properly. I want it to highlight only one of the enemies that are within range when the player character is looking at the enemy. This will be a way to let the player know which enemy is going to be hit when attacking and when it is within range to attack. I got it to only highlight one enemy but I can’t get it to stop highlighting if I look away to nothing. I also can’t get the range to work the way I want, as it starts highlighting enemies that the player is not looking at if I increase the range float to more then 100. I am using an arrow as a means of pointing forward for the script to work. I have the highlighting being done with a post-processing volume and highlights anything with the highlight tag. If anyone can help I would greatly appreciate it.