I could be getting a call in Facebook Messenger (heard the beeping), and accept the call on the computer, and start talking, only that now the iPad in the study room, and the iPhone in my jacket or pants keep on beeping NON-STOP.

I was at first going to just keep on talking and hope the beeping would stop after 30 seconds or so. No, the beeping kept on going even after 90 seconds or so, so I had to hunt down where the iPad is, and where the iPhone is, to stop them both, in order to carry on with the conversation. It turned out the beeping was only from the iPhone, but still. With telephones built in the 1970s, such a problem doesn’t exist — if you pick up one phone, the other phones will not keep on ringing.

Why accepting the call and the requests keep on beeping? Anyway to make it not beep like that?