A person, typically poor asks you for help. They present a lottery ticket and they don’t know what to do or say they can’t collect. Normally another person arrives to “help”. You three go check the ticket and it’s a winner, but you don’t notice that it’s not the same week, the ticket is not valid.
They want to sell the ticket to you for any kind of money or even jewelry. So, it takes two crooks for the scam to work, they and you.