Very sorry for your points loss and dropping from LG Level 9 to 8.
Nothing to worry as this has happened to many but in due course these points were reinstated.
Have you checked your Profile status under Number of Contributions? There is a high chance that this drop is due to decrease in points in ‘Answers’ category as I myself have witnessed this but in couple of days later all the decreased points were reinstated. In my case the drop was for 6000 points.