Ask for the name of a romance novel

This was to ask me about the search, but in the end, no one knew and closed it.
I remember a novel I read a few years ago. The elder sister and the younger sister were twins. The elder sister married into the palace in place of the younger sister, and the younger sister transmigrated to the modern world. At first, the emperor liked the younger sister, but when he realized that the one who entered the palace was not the younger sister, he gave the elder sister the cold shoulder. In the end, he finally liked the elder sister, and the younger sister also found someone she liked in the modern world.
Added:
At first, my sister also liked the emperor. The emperor didn't know that they had two daughters at home, so he issued an edict to let their daughters enter the palace. My sister thought that the emperor liked my sister, so she ran away from home. I forgot how she transmigrated to the modern world. The emperor was especially angry when he found out, so he ignored my sister. However, in the end, he still liked my sister.

Answer 1

The name of this romance novel was " The Royal Concubine ".