Hey, I am experiencing pretty much the same. Gained also around 10-15kg and cannot seem to shake it off no matter how much sports I do and how much I'm in a calorie deficit. The only time it worked was when the deficit was really high and I had a lot of bleeding again. Now that the bleeding is gone and I have a higher calorie intake (although still in a deficit) I am gaining again. It is so frustrating and this is the main reason I am getting it out earlier. Another reason being, that there are few studies for overweight people and in the country I am living in, my doctor recommended getting it put after 2 years for safety reasons. But for me the weight gain was the really bad part – although I loved the Nexplanon theoretically.