My Nokia 4.2 (Android One 9, security patch for December 5, 2019) is lately exhibiting a very weird behavior. If I dial a number, either using the keypad or from history or a contact, the screen blanks. I don't mean the autoblank when it's held to my face, I mean it goes black immediately. As a result, I can't hang up a call (or conference a third person, or anything).
If I tap power ... nothing happens. If I hold it to my face and remove it ... nothing. If I hold Power down, the phone doesn't turn off. When the other person hangs up, the screen turns back on. Sometimes if I press Power repeatedly I can get the screen on. Sometimes not.
Of course, I can plug in earbuds and use the earbud button to hang up, but for a quick call I hate having to do that.
Otherwise the phone mostly works OK. No other obviously incorrect behavior.
Odd. Any suggestions will be greatly appreciated.