On March 19, it was announced that Sojin left Dream T Company and signed with an acting agency Noon Company. The idol personally addressed the issue with a letter on Instagram.
Sojin explained she and the fellow Girl's Day members - Hyeri, Minah, and Yura -had many discussions and supported one another. She expressed appreciation to her members for supporting her decision.
She added, "I'm sorry to the many fans who've waited as we let go of our title as Girl's Day for a while. However, this is not the end of Girl's Day. It's just a break so please wait for the day we're together again even though it might take a long time. The members including myself will work our best at our individual positions and I pray there will be a day where we can deliver delightful news through a good opportunity."
Sojin ended the letter, stating, "I will be depicting a different story as 'Park So Jin' from now on. I love you. Thank you. And I'm sorry. This was Sojin. Please perceive me kindly til the end. Thank you."