Links are opening as localhost and not using hostname

We have upgraded xwiki from 8.x to 13.x version. It was a major upgrade. However, there are some internal links in the site which now opens as localhost and doesn’t use the domain/hostname.

From other forums topics, I saw that one which says about adding link or hostname to Descriptor section of admin. However, when I go to Descriptor, there is no links/hostname to edit.

Any help would be appreciated.

Thanks!