I'm certainly not surprised by the lack of efficacy of the PRP, since the science to support its cosmetic use lags woefully behind the heavy marketing to promote it. And I have been cautioning my readers for years already to exercise a great deal of buyer beware skepticism when it comes to PRP. Sorry. From what I can see, there is still quite a bit of hollowness under the eyes, meaning that the addition of an appropriate filler, properly injected in the area is likely to reduce the appearance of the dark circles. Likewise, a series of superficial peels supplemented by at-home use of prescription strength bleaching medications, such as azelaic acid, may prove further helpful. Make sure to consult with an experienced, board certified cosmetic dermatologist. Best of luck.