this is just to let you know what happened. I logged in to HRB 3D the other day,and I had a different Username and all achievements were gone. I contacted the support from "com2Us" and they were made aware of that bug. They stated to me on twitter, that they forwarded the problem to Google, and that it CAN HAPPEN TO ANYONE ANYYTIME right now. As soon as possible they will be updating. This is happening only on Android at the moment. Also, they stated that losing all achievements right now cant be reversed at the moment. But they are working on it!
Sad to hear, but good they do something!