I’ve stated answering all unknown calls with the phrase “make me a winner”. It’s a competition on several national radio stations that will pay you many thousands of pounds if you answer using that phrase. I don’t enter as I never gamble but I assure the caller that I’ve done everything correctly and want my money, then threaten to report them to the gambling commission using the number they called from. Either ends with them ending the call or trying to explain what they are selling and apologising because I say the winnings were going to pay for a hip replacement for my elderly mum

It’s quite fun really.