I'm in California, how does Samsung get away with selling junk that consistantly doesn't work? I now own this piece of junk(6days and joyously counting, sigh), thanks to the T mobile contract, and I have gotten to make 2 phone calls, and watched endless calls missed because a cloud pops up and I'm not allowed to see the green and red buttons, before the screen goes black, AGAIN.
Samsung sells this junk without a users manual, so therefore that gives them the right to employee people to answer the phones that can't speak English(yeah I know it didn't make sense to me either). By the way that is a LIE about random phone centers, in 3 days I had called Samsung 63 times, and all 63 times it went to the phillipines. I have spent entire days on hold with Samsung attempting to get this piece of junk to even function as a phone. I think when I'm finished with Samsung they will provide every user with a manual(at the time of sale), or the Department of Consumer Affairs will fine them out of business. Thanking you in advance for your attention.
Astronaut- I have the same sudden timeout problem - only in my case it is immediate. The moment I logon, the J3 LogsOff. Plus the phone no longer provides toll quality voice. There a few other problems all of which have developed in the J3 since the Android 7.1.1 was installed.
The J3 did have a number of issues to begin with but were resolved after numerous phone calls and finally replacing the SIM card with one that addressed AT&T instead of T-Mobile/Verizon. Then after a several months with the new SIM card and old Android 6.0.1 and the reception problems corrected - the Android 7.1.1 was downloaded.
Then these voice and timeout problems occured. It has to be in the software - not the J3. (But maybe both!)
My phone is a brand new j3 Luna pro. Stay alive did not work for my phone. It went dark after 10 seconds no matter what I did, so I searched for other softwares, found several and installed 3 or 4 activating them all. I have uninstalled one called Caffeine and another one, but still have three installed and active. Two of them are called Keep Screen On....one has a light bulb icon, the other a Sun smiley face. The third is just called Screen On. I wanted my phone to time out only when I tell it to, one of these three is working...not sure which, so I suggest you try one at a time. I was so frustrated by that time that I just downloaded them all and activated them all. It WAS A VERY ANNOYING problem to experience with a brand new phone!
Oh wow, alright. In that case, go ahead and backup and reset the phone. Let me know if the time out still doesn't adjust properly.