Why do I have this muscle bulge on my chin? How can I proceed? (Photo)

I had liposuction on my chin 5 months ago and everything healed great. However 3 days after receiving Botox recently I started to develop this strange chin bulge. We didn’t do botox on my chin the closet area injected was top of lip for a “lip flip”. It’s been 2 weeks and the bulge is still there. My injector thinks it is due to my surgery 5 months ago. Since it appeared after Botox I’m inclined to think it’s Botox related. Can anyone advise me on how to proceed? Thanks.