I have bought a Meizu M3s from eBay which worked flawlessly for around 6 months.
A few weeks ago it started to act weird, the WiFi would suddenly fail, but in a strange way, which I'll get to it in a moment, and the mBack/Fingerprint button started to fail as well, at the exact same time as the WiFi.
WiFi was connected, everything was correct and the upload and download arrow would appear on the small WiFi icon at the top, but pages wouldn't load and the Google Play Store would say I had no connection.
As for the mBack button, the touch/fingerprint function would stop working at exactly the same time as the WiFi issues happened.
To solve this, I simply went into my WiFi settings, advanced, and disabled all the settings that come turned on by default which were:
-Network notification, and
-Intelligent network switch
I had then put them back on to see if the issue fell on any of those options to be turned on, but nothing, the phone was working with the same settings it had before.
I had also downgraded and upgraded from several G versions of Flyme OS, from 18.104.22.168 to 22.214.171.124 and even 126.96.36.199 beta, all downloaded either from the Flyme OS official website or from Meizufans firmwares, and I kind of gave up after all those tries, the last one being the downgrade to 188.8.131.52 until I decided to update back to 184.108.40.206 and everything was working again.
1 or 2 hours later, the phone fell into the same no mBack/WiFi issues, but this time I noticed this opening the Play Store and it showing the no connection error, and once I got to Settings I noticed I couldn't go back with the mBack.
I could then fix this by changing settings on Advanced WiFi. At the time I'm writing this I only have "Disable when screen is locked" and everything is working fine for now.
I see many people blaming this on the actual hardware parts, but it seems like it's not... I wonder if someone else has even ran through this problem or have any idea how can these two things be related.
EDIT: Seems like this issue isn't directly related to WiFi, but network connectivity in general. I woke up this morning, the fingerprint scanned was working, I locked the phone again, stopped working.
I had then changed the settings again, but this time it didn't work.
But, the number you dial to see SIM card and connectivity details *#*#4636#*# does not work anymore, and it worked when I had the fingerprint/back button working. It simply worked by typing the number and a menu would come up, now it does nothing.
EDIT2: I was missing one more * (asterisk) on the end of this number… Should be * #* #4636#* #*
This code now works, but when I try to access Phone Information (first option) it just shows me a blank page. After a few minutes it says the process com.android.phone isn’t responding.
Also to mention the phone shuts down after some time as well, and (I’m not too sure about this one) turns back on after like 20 minutes or more.