In my forum, the message “The forums are currently locked and only available for read only access” is shown. 

The locked frag, Manage Groups and Forums -> Edit Forum -> Locked, is OFF. I never turned on the locked flag.  

The small lock icon is shown by the Add Topic button, still I can add new topic and can reply. Edit button is not appeared.

Then I delete forum, and create again with the same name. The locked situation is not changed.

How can I off this incomplete lock state? its strange.