BATTERY DRAIN

We have 18 company Iphones, 14 we're upgraded to 9.3.5 by the doctors. Since then the battery drains in 3 to 4 hours, WHICH USUALLY TAKE A DAY OR TWO TO DRAIN! We have done

1. Hard Reset

2. Restore phone from Itunes

3. Restore phone from Icloud

4. Remove ALL apps on the background

ALL iphone except the 3 iphone 5 (OLD) are ok because the Medical Asst did not upgrade.

I would like to get instruction how to revert back please.

FYI: So far I have found atleast 100% complain about this updates and previous one and APPLE HAS JUST THREW THE PROBLEM BACK TO THE CONSUMERS!.

IF APPLE CANT BACK UP THERE PRODUCT...SAY SO THERE ARE A LOT OF PHONES OUT THERE! Quit ingnoring and blaming the consumers.

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