suspect that you have got
dashboard>settings>forums>forum root slug>forum prefix set to not show, so it is creating a duplicate
I tried it and didn’t work. I tried with ticking and un ticking the option ” Prefix all forum content with the Forum Root slug (Recommended)” and nothing changed
The “Forum Root” is “forums” and the “Prefix all forum content with the Forum Root slug (Recommended)” is checked.
I wish I can add a screenshot here but it doesn’t seem I can do that
ok, not quite sure what is happening
1. are you using caching software? If so purge
2. try dashboard>settings>permalinks and just click save – this will reset the links
if both those fail, then it could be a theme or plugin issue
Plugins
Deactivate all but bbpress and see if this fixes. if it does, re-enable one at a time to see which is causing the error.
Themes
If plugins don’t pinpoint the problem, as a test switch to a default theme such as twentyfifteen, and see if this fixes.
Then come back
I figured out the issue in the permalinks. I wanted to remove the word “Category” from the links of the posts so I found an article in WordPress support forums that I have to write a dot “.” in the field
Category base in the permalinks and it worked to remove the word category
but now I tried to remove the dot and the word category is back to the links but the issue of the bbpress is fixed. so the issue was with that “.”
How can I remove the word category from the links then without the dot?
sorry not in my skill set !