XF 1.1 Cannot create threads

After I write the thread and clicked the create threads button the particular thread is not posting in some forums/subforums in my forum. This is happening only in few forums. I checked the forum permissions, but they are same as the other forums. I tried by clearing the browser cache and rebuilding cache of the forum as well. Not only that, in this forums/subforums, when I put the cursor on Alerts and inbox they expands the menu and just shows loading icon as shown below.

This issue is happening only in some of forums/subforums. Please help me to resolve this.