I have no idea what happened.
The only thing I did was to charge my phone yesterday night, and this morning, it apparently had reset itself (but not completely).
A lot of my settings went back to the default (e.g. I set no vibration for the phone, but it went back to have vibrations, no dial tones to have dial tones, etc).
I can hear notifications, but see no notifications on the notifications bar. When I tried to pull down the notification meu, it doesn't get pull down at all. All I see is a set of default icons (Wifi, Mobile Data, Battery Charging Status, Do Not Disturb, Torchlight, Screen Rotation). When I press on the Settings (gear) icon, nothing could be displayed.
When I go to the Developer Options screen, I get a "Developer options is not available for this user" error. Previously, I have a list of options.
Additionally, I can't install apps, Google Maps can't navigate (but GPS is working fine), mobile data keeps switching off by itself, Gmail not syncing, and a whole lot of other strange problems, all of which were working fine until this happens.
How can I fix this?
This happens a bit regularly. There's no telling when it will happen. Think I may have a faulty phone...
You should probably bring it to a service centre. Anyway, I believe this happens because your phone thinks it was factory reset and not set up yet. If you want a quick fix, then go to this forum thread and take a look at the third post: https://forums.androidcentral.com/samsung-galaxy-s7/659407-s7-edge-not-showing-notifications-tray-recent-apps-button-settings-button-dnt-work.html. Hope it helps.
The first time when this happens, I Googled for this problem and saw the S7 Edge thread. I tried, but failed. In fact, I can't even install apps...
So every time this happens, I have to factory reset the phone. It's pretty annoying. The phone is only a few months old and I have performed factory resets a few times already.
There's also no particular symptom of when it might happen either. Sometimes an app crash will trigger it, sometimes when I leave it overnight charging, other times, a random reboot and it "resets" itself - but to a non-working state.
@user1509072882486: Nope. I only have one user profile.