Why do fortune tellers calculate according to the lunar calendar instead of the solar calendar?

Generally, fortune-telling in China is based on people's gossip. In fact, from the root, fortune telling has a great relationship with the Book of Changes, because the Book of Changes is a book that guides how to improve life energy and teaches people how to be a man and adapt to life. It involves three contents: practice, philosophy and divination. Therefore, it has become a classic of Taoism, Confucianism and Yinshu, and the three religions have different understandings and applications in their respective fields. It is the experience of the ancients to sum up the laws of the movement of the sun and the moon. Our lunar calendar is based on the laws of the moon's movement. Therefore, ancient divination was based on the lunar calendar. These are my humble opinions.