People lie for many different reasons. If you find out that the person you know is lying to you, you can send him/her the Lying Face emoji 🤥. This emoji has a yellow face with large eyes, raised eyebrows, and long nose. The latter feature is akin to the popular cartoon character, Pinocchio.
You can use it if you think you are a liar, or if the person you are talking to tell something about you, and you think it is not true, then you can use the Lying Face emoji 🤥.