.
The cause of her death remains a mystery.
Oh often shared videos documenting her job as a weather forecaster.
She also loved sports and shared photos from her daily runs.
Her final post on September 12 was an image of her while on a run, promoting a set of earphones.
In 2019, she participated in a Korean beauty pageant called Spring Fragrance Selection Competition and won first prize.
Actress & singer found dead in bath hours before she was due to go on stageShe has also participated in a supermodel competition.
After learning of the news about her death, her fans took to the comments on her final post.
One fan said: “I was surprised to receive the news. I am speechless. My hand is shaking.
“Rest in peace.”
“I was very surprised. This is so unbelievable," added a second.
"Close your eyes and hope you are safe out there."
I was surprised to receive the news. I am speechless. My hand is shaking.
Fan of Oh Yo-anna
Someone else said: “MBC employees must have been very surprised. Rest in peace sister.”
News of Yo-anna's death comes as several tragedies have struck young women recently.
A 20-year-old singer died after receiving a "neck twisting" massage.
And a 33-year-old actress on a retreat died after consuming frog venom during a "healing ritual."