Is it the locked one? The trigger condition must be all, that is, all four people must be present. Dialogue with wine merchants in Kaifeng triggered the task. Talk to the wine merchants to get tips on the stone tablet and treasure, and then go to the stone tablet to get the whereabouts of the stone tablet fragments. Talk to street children in the east of the city, buy some rare sweets from candy merchants for Xiaotang, get fragments of stone tablets, get tips from restaurant stone tablets, get tips from the city gate stone tablets in front of the restaurant stone tablets, and when you come to the city gate stone tablets, you will get a key to open the locked box in that yard. It's actually just a sideline.