Across the game I've found a lot of NPCs dont seem to be on the map, mostly Witcher contract givers and Gwent players (e.g. the Gwent playing soothsayer in Benek, the contacts for Jenny O' The Woods and the Phantom of the Trade Route, etc. etc.). I still have the quest marker indicating where the NPC should be, but when I go there - nothing! I wait and wait, go somewhere and come back, and the game still points me at an empty stool.

Is there something I'm doing wrong? It seems like I'm the only person on the internet with this problem.

A lot of people do not stay in one place 24/7, even the vendors in the Novigrad market place are only there during the day time.