My Fitbit Blaze has suddenly stopped registering heartbeat or sleep for the last 5 days. During the day when active it has taken some intermittent heartbeat readings but these are interrupted and not continuous. When I do get intermittent readings they are way high and then suddenly drop to normal levels. I know the two are connected. I haven't changed anything I am doing with it or how I am wearing it. I did a hard reset, shutdown, clean the back, change the placement, etc. Seems like something is broken.