Battery issues S24+

I got a S24+ about half a year ago and everything was fine until a couple of weeks ago. There are 2 major issues:

1. The phone charges super slowly. It used to fast charge but now it takes at least an hour to get from 60% to 90%. I tried multiple Samsung chargers and cables, so it does not seem to be related to that. Nothing changed in the settings, fast charging is on. Also toggled it off and on but it did not work.

2. During the night, my phone loses 30+% of battery percentage. I have no apps in use (it also tells me that when I check why the battery drained so much, it's got nothing to tell me). Workprofile is off. WiFi and data off..

Anyone any clue why this could be happening all of a sudden? Might a software update be responsible?