Permalink Issue | Accessing nggallery Gallery Page

Hi,

I for the life of me cannot figure out how permalinks work. I had to migrate a site from an old server to a new server, and now permalinks do not work as they used to.

In brief, a link from a photo page (https://nmdance.com/photos/gallery/) to a nggallery gallery index (https://nmdance.com/photos/gallery/nggallery/adc-photos-2/beach-party-2014) only kicks back to the section index page (again, https://nmdance.com/photos/gallery/). I have no idea what I need to do to fix this.

The permalink structure on the site is:
/%category%/%postname%/

I admin this site for an org I work with as a volunteer, so I am working on it for free, and just really need some help.

Thank you much.
Bruce