After 5 years waiting for a debut, trainee Hina and a member of the SM Rookies group may have left SM Entertainment.
https://www.instagram.com/p/CGWSBzlp6jX/
We can see that she opened her own Instagram account and other SM trainees are following her. Also, Koeun (former of Rookies) shared a post where we can see Hina and other girls posing.
https://www.instagram.com/p/CGXvFKHnxke/
It is just a rumour, there has not been an official statement that confirms Hina left the label, but if she did, the only SM Rookies member remains is Ningning; that has 18 years old and has trained for 4 years.
