Oops! The King is in Love (2020) - Oops, My Heart is Beating
Yan Zhixia is a the daughter of a minister that loves money and disguises herself as a man in order to work in the royal palace. She mistakenly becomes the eunuch of the Emperor, and with his help, slowly becomes the Head eunuch. However she discovers that actually, Yan Jin knew of her true identity long time ago.