What about sadness?

Sadness Microexpression: → Inner corners of the eyebrows are drawn in and then up. → The skin below the eyebrows is triangulated, with the inner corner up. → Corners of the lips are drawn down. → Jaw comes up. → Lower lip pouts out. This microexpression is one of the hardest to identify because it's not very noticeable. If you notice customers displaying this microexpression, pay attention to your surroundings to find what evoked this emotion. Put your feelings aside and listen to your customer, find out what made them feel sad, be empathic, and show you are there to help them.

Check the video below for more examples: https://www.youtube.com/watch?v=34rqQEkuhK4

Source: Van Edwards, Vanessa. "The Definitive Guide to Reading Microexpressions (Facial Expressions)" on scienceofpeople.com Photos by Andrea Piacquadio from Pexels