My Lumia 640XL battery dropping so fast while doing nothing.

[wphilal]

Hello awesome windows phone people,

I have been using my 640XL for a while and now i'm running Windows10 Mobile, and the phone is great, but since yesterday I've noticed my battery dropping so fast while doing nothing! (no wifi, battery saver on, only gsm, and the phone is closed (locked screen)) and this happened suddenly, usually i have no running background process, the battery takes the normal time to get fully charged and i believe the problem is not with the battery, but it seems there is a stuck process consuming the battery(actually eating it) i don't know what to do, the average life time for my battery is two days!, i don't know if soft reset can solve this issue.

Thanks in advance.