Edit: I also happened to charged it in my car’s 12v socket using an ordinary usb adapter then also noticed after a few days it charged slow already. Could this be the possible reason also?
I just recently experienced this about a month ago where prior to this i’m fast charging in just 2 hours more or less while now i’m charging more than 6 hours to get fully charged. I noticed that before this, I got an update, then this slow charging started. Its not a problem to my charger and its chord because I tried charging it to my gf’s phone and it filled her phone up in just less than 2 hours. I also dont think it’s a problem to my phone’s battery because its relatively new like no more than 2 years. What could have been the problem? Are other people experiencing the same issue as well? I’m on android v.10 if it helps.