Spam not in default folder on mail Os X

Spam not in default folder on mail Os X

Hi everyone,
My default spam folder (imap) is not synchronized with the online folder under Mail for Os X 10.9.5 (Mavericks)
Send messages folder, markers and all others are ok, while only spam folder is not inside the default folder but is visible in the bottom folder as you can see in attachments where you find also my setting.

It is not a real problem, but is annoying because some notifications remain on my dock, and I am obliged to check and open spam folder to solve manually the issue