It would really help to have photos, with that said it sounds like you may be a candidate for revision liposuction. Contact a plastic surgeon in your area that specializes in liposuction
Sorry that you have experienced a complication / complications following your liposuction procedures. Obviously photos and an exam would be helpful but it sounds like placing the fat back and getting it to live is your best option. Consult PS's in your area till you find someone with lots of experience with redo's.
What can I do about over liposuction in one banana roll?
Fat grafting to the dent and to the buttocks would be the most likely treatment to help.
Liposuction results are highly surgeon dependent. Find a board certified plastic
surgeon who performs hundreds of liposuction and liposuction revision
procedures each year. Then look at the plastic surgeon's website before
and after photo galleries to get a sense of who can deliver the
Kenneth Hughes, MD
Los Angeles, CA