Can someone explain to me why I lost my projection so fast (in less then 3 months)?

I am not sure why you specifically had such a drastic volume loss after having a BBL, but I can just tell you some generalized information regarding the procedure. I never recommend that patients gain weight in order to provide more fat to be liposuctioned and transferred to the buttocks. The reason is that when you go back to your normal lifestyle after the surgery (whether that includes working out or dieting), you will just lose the weight that was gained. When you lose the weight that was gained, the volume is lost in your buttocks where the fat that was transferred. Fat transfer to the buttocks also has ~50% loss in volume even with the best technique. This loss in volume occurs over the first 3 months after the surgery. Unless your lifestyle changes, the size after 3 months should be stable. It is very important after the procedure that you follow your surgeon's recommendations. The day of surgery and immediately after the procedure the buttocks will look very large as some of this volume is from swelling. Therefore, not all of the added volume that is seen immediately post op is from the injected fat. Over the 4-6 weeks following the surgery, the swelling goes down. I always tell my patients to expect a significantly smaller volume than what they see the day of surgery. The most important aspect of plastic surgery aside from finding the right surgeon is realistic expectations. 

1.- did you go with a certified plastic aesthetic surgeon certified by ASAPS ?2.- di you utilized  autologus fat plus plastma or another syntetic product?3.- most of failure of this  procedure  are  to put the fat superficial and most be deep on the muscle and superfitialhope  this  might  help to get your answers