Recently Samsung has been notified that some users with J3 2016 device(SM-J320F) based on ‘EE’ operator have experienced the symptom of rapid battery drain. For users affected by the symptom, Samsung is scheduled to release a new software update which will be available in the coming weeks (The end of June).
Therefore, please check for updates to your device SW regularly via the FOTA or Smart Switch PC.
Samsung encourages users to keep your software and apps updated to latest version. Samsung is committed to providing the best possible mobile experience to customers. If the problem is still not resolved after software update, please visit to the Authorized Samsung Service Center with device and check whether your device has any problem.