Pages are not found

Using 4.5.2 and Bridge theme.

I tried to edit SEO-settings and amongst other things edited the Yoast settings. Found out that none of the pages work anymore, only the first page can be found. I edited the URL-setting (Strip the category page etc..) could this be the reason? OR is it something else I did and didn’t relize. Or it it the webserver?

Disabling or uninstalling the plugins does not help.