I got some info from JaME U.K. (the best news site for all things J-music) about our beloved bassist.
Unfortunately hoa nhài bạn will be taking a break from band activity due to his poor health.
Here's a link to the original bài viết so bạn can read it for yourselves...
link
Keep hoa nhài bạn in your thoughts! Hopefully he will be feeling better before too long.
hoa nhài bạn が お大事に!!
(get well soon hoa nhài bạn {i hope...correct me if i'm wrong....})