Urmila was the second daughter of King Janaka, the younger sister of Princess Sita and wife of Lakshman in Ramayan. So how did Urmila did in the Ramayana?
When Lakshmana drowned himself in the Sarayu River after the death of Bhagavan Sri Rama, Urmila ended her life by jumping into the fire. There is no historical evidence to prove this.
Lakshmana ended his life by entering Sarayu River when he realized it was time for his incarnation to come to an end. So it is believed that Urmila too might have realized that it was time for her to depart from the world. It must be noted that many characters in the Ramayana were avatars or amsha avatars of one or other gods or goddesses.
Bhagvan Sri Ram had given Urmila a boon that she will be worshipped in Kali Yuga as the Mahaprasad in Puri Jagannath Temple. (You can read the story of Puri Jagannath Mahaprasad here).