I am using LG V20, model number is LG-F800K. 2 days ago, I installed the official update to Android 9. However after the update, my phone became battery drained faster and worked slower than before. I have tried at least the following 3 ways to try to get back to Android 7 or Android 8:
- https://forum.xda-developers.com/v20/how-to/guide-lg-v20-to-life-t3827732 -> "Download failed" error.
- https://lg-firmwares.com/how-to-flash/#how-to-flash-new -> Unknown model.
- https://lg-firmwares.com/how-to-flash/#how-to-flash-old -> Error "could not connect to server".
As of now, I really don't know how to reduce the Android version on this device?
I would appreciate your help.