I’m not sure if this is right but it has been right so far (We know how that goes with this Stock Android issue.) Anyway, my ZTE was busted in the charge port for a few months and I had this crappy replacement phone for it. The ZTE was already doing the Stock Android issue before this happened. I got the charge port fixed and then reset the phone and reconnected the sim card from the crappy phone back to the ZTE. So far I haven’t had any Stock Android issues.
This is not what I’m talking about, btw. Since I reset the phone I have yet to do any of the following: Change the wallpaper, which I might do to see; but more importantly, I DO NOT have the Facebook App on my phone. I use Chrome and go to Facebook that way. Knowing facebook and its constant updates, I have a feeling having that downloaded as an app (as well as having Messenger take control of your SMS) could be causing this issue. I’ll look into it further, but I have this feeling that facebook is the problem. The app that is. We’ll keep updating as the days go by.