I have a number of treatment protocols for non invasive breast firming and lifting, but unfortunately, for major weight loss, it is usually quite difficult to get significant or what I would consider pleasing results with non invasive treatments.
Surgery to address this is a breast lift or mastopexy.
I find this link a very good source of information:
https://www.plasticsurgery.org/cosmetic-procedures/breast-lift
Best wishes.
