Could my muscle have slipped off the angle and if so how do I correct this?

I had mandibular angle implants over a year ago. I started to experience tightness on my left side with my jaw muscles. Upon further inspection my masseter muscle on the left side sits a cm or so in front of the jaw angle whereas on the right side it goes all the way to the angle and feels like in envelopes it. Could my muscle have slipped off the angle, if so how do I correct this, is it a complex procedure etc