Cannot create Boss room

Since 3 hours ago, no one in our server can create a room for Boss battle. We can see MANY rooms (about 50) there but cannot join. The message says "Boss is in cooling down status now".

I'm from server 15.

After one night, this issue still persists, I can see many players in our server complaining about it.

Why not any support respond to this thread? Is this thread invisible to them or sth.?

Support54:
"Please log in your dragon account to contact your server support.
Click the green circle on the right top of the main screen, then click "help" and "support" button. Pull the scroll bar to the bottom, click "clicking here", then you can write the letter to your server support."

Support54:
"Please log in your dragon account to contact your server support.
Click the green circle on the right top of the main screen, then click "help" and "support" button. Pull the scroll bar to the bottom, click "clicking here", then you can write the letter to your server support."

Thanks, it is working today.