Hi NathalieR,
i had similar problems the last 4 weeks. Two weeks ago the screen than turned completley black. I conntacted the support team, however i only got the generic answers after about a week:
Blockquote
Step 1
To help you further and to improve our product quality, we would really appreciate if you could provide the following details:
Can you tell us which app/steps you performed before your Fairphone 3 showed this issue?
Step 2
Sometimes this issue can be caused by the operative system being corrupted. We suggest you refreshing the operative system of your phone.
Make a backup of your personal data.
Refresh your operating system by following the procedure of this article: Install Fairphone OS on Fairphone 3 using a computer.
Reset your Fairphone 3 to its factory settings. This will wipe all your personal data.
Step 3
Check if the behavior remains.
If it does, could you provide us with pictures or a short video to show us the symptoms?
Try to keep the video size below 20 MB. If the file is bigger than 20 MB, you can use our Fairphone Fileshare portal to upload your files. Please click here and follow the instructions.
I also tried the disassemble/assembling tricks, the battry removal and so on. So far nothing worked. Yesterday, out of desperation, i tried it once more and realized that on the display there is a small silver coverage. This coverage seems to secure an inner connector of the display. I pressed the silver coverage gently down and felt a small click. I assembled the phone back togehter and it worked (even without the screws keeping everything in place.). So the phone is now running perfectly again for about 24h. Probably this can also help you resolve your problem.
Cheers from Germany,
Moaxle