How to customize the permalinks slugs
In order to customize the permalinks of the listings post type and all of the listings taxonomies, login into your WordPress admin panel. Navigate to Settings → Posterno → Listings and locate the slug settings.
Type in the text you wish to use for each slug and then save the changes.
After making changes to the slugs you must re-save your permalink settings. Navigate to Settings → Permalinks and simply press the save button at the bottom of the page.