Wonderful Nightmare

Misseu waipeu is a movie starring Uhm Junghwa, Song Seung-heon, and Yoo-mil Park. A clerical error in heaven leads to Yeon-woo's untimely death. To fix the mistake, she must live as another woman for a month.
When a woman dies after a mistake by personalities in the afterlife, she needs to exist as a different woman for a while.