Defender Merc acting odd lately

When I was first playing the Defenders I would find were great. They kept the mobs at a location. only moving when there were charge attacks that relocated the mob.
As of 1-11-21 my Defender mercs have been having this habit of running back to me. sometimes Yo-yoing back and forth without attacking the mob.
since I am a support caster this is really, really frustrating with AoEs psuddenly pointed at me while I am mid-cast.

 

Defender mercenary acting that way because their first attack miss, and they will keep running back and forth until the attack land a "hit" at least once.

2 ways for this, get defender mercenary with high accuracy (like 2.5k), or
barehand defender mercenary because it has innate 50% hit chance.

edit: I forgot to mention one more possibility. You are too far away from the enemies, since mercenary can only several meter away from you

 

I used barehand defender effectively for a while, but at higher level bosses it had difficulty pulling aggro until it cast a skill. I changed to 1.85k accuracy using ice cream cone knuckles and it worked better. It should also have at least 1k aspd and several interrupt skills in addition to provoke to be used when needed on different bosses, especially if you want to break.