What is the star below the secret star of Lagerstroemia indica?

This is the three walls and twenty-eight lodges in ancient China. Sanyuan is the sky area near Polaris, while Erbasu is the sky area in four directions around vernal equinox. The three walls are Wei Zi Wall, Qiu Wall and Shi Tian Wall. Twenty-eight lodgings are divided into seven lodgings in East Qinglong, seven lodgings in South Suzaku, seven lodgings in West White Tiger and seven lodgings in North Xuanwu. I remember there is no star of Wei Zi, but there is Wei Zi Garden. Ziwei Garden includes Polaris. The Polaris is motionless, so it is regarded as the symbol of the emperor. China pays attention to the harmony between man and nature, and the Forbidden City corresponds to Ziwei Garden. The celestial pole is the third star of the Big Dipper. I don't remember which wall it belongs to.