After update my phone is going downhill. Wi-Fi and data don't work properly and youtube won't work at all on data. Sometimes I haveto activate and deactivate flight mode and will work at Times but not always. I tried all the steps from google but nothing works.
If all fails, best bet is to move, copy and paste ALL your data to somewhere safe, like a laptop. Then, factory reset the phone :). If this STILL fails, hopefully you are under warranty or a care plan, to get another phone lol.