Has anyone had any issues with the Lollipop updated? Since the update, my S5 randomly reboots (6 times in 90 minutes last night), is very sluggish (can't tell if slow or non-responsive), and has poor battery life. The HeartRate LED lights up every time it enters shirt pocket. Is there any way to roll back the update? Loved this phone until the update - now it's constantly rebooting, and is becoming useless.