Got a Note 3 on ATT and this is my 3rd one. Tired one on ATT and took it back and got one on Verizon and now I'm back on ATT because of the unlimited data plan. Any way I've never had this problem with the first two so I'm not sure what is going on. Phone stays awake and screen stays on. Timer is set to 30 seconds and I switch it and changed it back again thinking something just didn't work right. Now until I did this I never switched any of the settings. Only had the phone for 5 days now and had meeting all weekend so not real time to play with it until now. Just so it is clear what I'm saying is the screen just stays on and it's on the home screen.