I have the same problem... I have iphone 8 plus and i unfortunately updated my iPhone to ios 14.0.1 and after this update my battery drains so fast it was not like this before. guys I just switched from Samsung to iphone a few months back because Samsung battery is very bad and i was a big fan of android, but after i switched to iphone i was very satisfied with my 8 plus battery performance but now i feel disappointed after this ios version 14.0.1 Please guys fix this issue i just loved iphone products, i don't want to feel that it was a bad decision to choose apple.