Samsung Galaxy A9 BATTERY DRAIN PROBLEM

A

AC Question

Hi fellow android users.

I'm android user since 2010.
Last year I bought the Samsung galaxy A9. First 6 months of the usage was great great, especially the battery life was stellar, 2 full days, no problem.

But after upgrading to Android version 6.0.1, my battery life took a huge hit!
Not even a full day!
And the reason for this is: ANDROID OS keeps running in the background and sucks battery like nothing. In 14h usage, android os keeps the phone awake like 11h.

Please I need help for this problem.

Thank you all.