Just wanted to update to say I can change my wallpaper by going to settings, lock screen, wallpaper and choosing wallpaper gallery, which is what the phone came pre loaded with. Choosing gallery gets the same result as before... The phone says it changes it but really doesn't.
Sent from my LG-D851 using XDA Free mobile app
LG G3- D851
LG G2- D801, HTC Amaze 4G