I can see in the photo the difference. I would like to know if these look difference with the arms at the sides. If that is the case I would recommend nothing other than continued massage.
If these look the same with the arms down, and have not changed over recent months, I think a visit to our surgeon is in order. If this is a capsular contracture, there are some remedies that can be tried short of surgery. If both implants are soft, it may be that only a repositioning of the higher implant at surgery can resolve this.
Thanks for your question, and best wishes.