"I never hear my phone", I remarked, as I noticed that I had missed a call at about 7pm.
"Oh, that was me", said one chap, "I phoned from the corner of the street, but then I realised I was not lost after all."
"Oh, that's because you have it set to DO NOT DISTURB", said someone else, "See!"
"Oh, I see", I said, though I didn't really see at all.
"And I never hear it when Alan sends me a text message", said Pat.
"Oh, look, you have it set for do not disturb for him - oh yes, and for me" observed Catrin.
Honestly, it's like teaching your grandmother to use a spreadsheet.