lately my fairphone does some weird stuff. Whenever I call somebody and hold it to my ear the display is blackening as it should be. The problem is, it is not possible to revive the screen when I want to stop calling. In some cases I was stuck for five minutes at the mailbox guy/girl. All telephone features are working nicely (e.g. I hear the other party, I hear the ringtone, I hear messages from provider).
Does somebody know how to deal with this?