Dit heeft waarschijnlijk te maken met de proximity sensor die niet goed ingesteld is. Er zijn een aantal berichten op dit forum over dit soort problemen:
Solution: Please follow the official troubleshooting tool .
archived text Besides a badly calibrated sensor the next most common reason for this issue is dust between the proximity sensor and the screen. For more info check <a href="https://forum.fairphone.com/t/fp2-screen-cant-be-reactivated-during-after-calls-see-first-post-for-workarounds/11874/148?u=paulakreuzer">this post</a>.
Cleaning tips:
Clean the screen of your phone, especially the part where the proximity sensor…
When my phone connects to a caller, the screen goes blank and insensitive.
I’m told this is due to the proximity sensor needing to be calibrated, and that there is a tool to do this. Where do I find it, and how do I do it?
De oplossing is meestal het kalibreren van de sensor.