Q. Scrolling through my WhatsApp contacts, I have found a name I don’t recognise but when I click on the profile I can see it is a very pretty girl. I suspect I may have met her on a night out when I might have had too much to drink which would account for me not remembering who she is. Because I don’t know how long ago this meeting was, or even where it was, I’m not sure if I can now send her a message and start a conversation. What do you think, Mary?

– E.L., London SW11

A. Send a lunchtime WhatsApp saying, ‘I’m standing outside the Wolseley [or similar desirable hotspot]. Where are you?’ This will prompt an urgent confused response. Text back, ‘So sorry. I meant to send that message to someone else. He’s just arrived. But how nice to hear from you. What have you been up to?’ Her answer will give you a clue as to where you met and pave the way for you to take things further.

Q. We have a daily woman who comes once a week to our London flat. We tend to leave very early in the morning so we rarely overlap with her. Our problem is that neither of us knows what her name is – we pay in cash which we just leave on the kitchen table – and since she has been coming for at least six months, we feel we cannot now ask her. What should we do?

– Name and address withheld

A. Invite a friend to stay the night in your flat and make him- or herself at home there the following day. That person can be the one to elicit the name when they have to introduce themselves since you will be out.

Q. I recently attended a colleague’s wedding. At dinner, the man who was supposed to be sitting on my left had messaged that he would be late, so there was a gap left. The man on my other side was the MC, who therefore barely sat down. As it happened, the latecomer did not arrive until we were at the cheese course. The round tables seated ten and were so broad in diameter that it was impossible to talk to anyone unless they were actually sitting right beside you. I felt I was attracting pitying glances from other tables as I sat there on my own. I wonder what you would have done, Mary?

– A. H-S., East Sussex

A. This was not a matter for self-pity. It was your hosts who would have been mortified to see you marooned. Out of consideration for them, you should have had no compunction in sliding into the place of the expected latecomer. As soon as he arrived, you could have moved back – or indeed let him occupy your intended seat next to the absent MC.