In China mythology, why does the phoenix symbolize auspiciousness?

According to ancient books, Phoenix is a beautiful bird, and its singing and manners are the king of birds. It can bring auspicious feelings to the world, and at the same time it has the special spirituality of' don't be an unripe phoenix tree, don't eat bamboo, and don't drink water from a spring'. Because it is the length of feather worm, it gradually becomes a pair with the legendary dragon with the length of scale worm. Phoenix is the legendary king of birds, the male is "phoenix" and the female is "phoenix". The ancients regarded the phoenix as a symbol of kindness and good luck. Phoenix is the Guardian in ancient mythology. Phoenix, the Queen of Nine Days, is called the Virgin of Nine Days in Xuan Nv. There are two incarnations, namely, golden phoenix Fairy, Qingluan Boy who serves the goddess of creation, and Qingluan Boy who guards the gate of Nuwa Palace. Phoenix is one of them. It is called the Nine-Day Xuan Nv, also known as the Nine-Day Virgin. The universe is chaotic (the sun), holding the phoenix nirvana and destroying Zhu Pei.