Why is my battery life draining so fast? (Huawei P9 Lite Mini)

[Android Central Question]

I bought Huawei P9 Lite Mini two months ago and battery was good. But last two days (after new update) my phone loses 30% over night (I turned off Wi-Fi). And battery is draining so fast. Can new update be the problem or is the problem in phone? Please help.

 

[belodion]

What do your battery usage stats indicate as having used the charge? That is in Settings > Battery.