The princess is talking to her dad and she wants him to find the knight who saved her.
When the knight was born, his mother left him because he was born as a male. Because his mother left him, he was raised by his father. After the knight's mother left, his father stopped caring about him and what he did.
One day, while the knight was cleaning a roof for pay, he fell from a great height. When he fell, he hit the ground head first. He then forgot who he was and where he came from, which is why he doesn't know his true identity as an adult.