I have put the forum on a subpage: http://solcellepriser.dk/debat-og-forum-for-solceller/skriv-indlaeg/

But all the links to the topics are not working, because they have http://solcellepriser.dk/forum in the beginning.

I try to go to admin: Forum -> Integration -> Page and permalink and there I choose “debat-og-forum-for-solceller/skriv-indlaeg/” in the dropdown and I save the settings and nothing changes.

I also try the “Update Forum Permalink” on that page, but that doesn’t help.

I go to WPs permalinks settings and save those and that doesn’t help.

The “Redirect ugly URL’s to clean permalinks.” option in Yoasts SEO is not checked.

There’s a help text to the “WP Forum Page Details” section on the “Integration – Page and Permalink” page, which I don’t quite understand: “Note also that if your choice of a forum page is a ‘sub-page’ then the slug will need to use both parent and child slugs.”

Where would I put the parent and child slugs?