@mrlen Legacy Forums support is removed with BuddyPress v3.0.0 and theme also need to update accordingly. Please check with your theme support
For details, you can check https://bpdevel.wordpress.com/2017/12/07/legacy-forums-support-will-be/
Thanks @vapvarun. I checked out that link and started to follow the instructions for migrating. But then I found that I am already using bbPress 2.5.14. So it seems I am not using the old bbPress.
Also, when I get to step 3:
[code]
(3) Remove “Forums” page from BuddyPress
In the the WP admin dashboard navigate to “Settings > BuddyPress“. Click on the “Pages” tab.
Under “Discussion Forums“, select “None” and save.
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There is no such “Discussion Forums” section.
So I think there must be some other problem.
We don’t have enough information to figure out what the cause might be yet, I think we will need to try to reproduce the problem, but it doesn’t seem to be unique to your site, so I’ve created a bug report at https://buddypress.trac.wordpress.org/ticket/7844 — please keep an eye on that for updates.
I can give you access to my WordPress so you can look.