My main (Wyvrn) targets mob "A" and I hit "2" on my keyboard..

2 on my clones is:
/assist Wyvrn
/petattack


95% of the time everything is perfect... but every once in a while instead of attacking my target they go running off to attack another mob close by with the same name... I'm 100% sure i'm not missclicking... That was the first thing I checked

Is this an assist bug?
Anyone else have this problem?