Excuse my total ignorance on this, I'm old! Got stuck in a traffic jam tonight, so used the phone in the car to call home. All well, contact list there, call initiated, called party hung up, leaving me listening to a monotonous tone. Only way I could find to end the call was by ending it on the actual phone handset itself. What did I miss? Doesn't say anything helpful in the manual, as far as I can find.