Welcome to the CH F@H group I've got the icon added to your profile.
Regarding your question, sometimes when the computer is restarted it will reset F@H stats because the F@H client is abnormally stopped causing it to loose all progress. If you continue to experience the issue in the future one tip is to close the F@H client before restarting your computer. By closing the client it properly it will not loose any of its current progress.
Normally restarting the computer shouldn't cause this to happen, it should be able to close properly, but something else running on the computer could be causing the abnormal termination.
Hope that helps.