Yes, that one! Because he refused to give the enchantress refuge and begged for forgiveness once she found out she was beautiful, she had cursed him. She wanted him to see that beauty is on the inside and that he had judged someone by her appearance despite a plea for help.

[Though that part was a lie and she was testing him, but details.]

The heroine, Bella, instead falls in love with the monster, seeing that he is truly kind and not judging based on his appearance.