For a few weeks I have been having bad problems with my battery draining. It happens the majority of the time, but occasionally will not happen for a little while. At the times when the battery does drain really quickly (which is almost always,) when I look at the battery manager, the Android OS is always over 70% and sometimes even 80%, which when it is working correctly, is not the case. I do not change any settings or turn on any apps when having this problem. It starts on its own sometimes when the phone turns on and off (sometimes by itself) and I think sometimes randomly also.
Any ideas as to why this is happening and how I can fix it?