The site has been enabled with syncing for permissions as described in this article: SiteSync: How to sync users, roles and permissions for roles?

The sync options appear on the SiteSync screen on staging, but when attempting to sync the users, no items are synced. Is it possible that production is not getting the setting to allow this?

 Having verified that the SiteSyncConfig.config contains the security snap-in option (securitySnapInSyncEnabled="True") and is configured properly for both Staging and Production environments.

The missing roles in the target environment, which prevented the synchronization of users, roles, and permissions.

1.Recreate the missing roles in the target (production) environment using the provided API code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Telerik.Sitefinity.Security;

namespace SitefinityWebApp
{
    public partial class CreateCustomRoles : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            CreateRole(new Guid("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"), "Custom Role");           
        }

        public void CreateRole(Guid newId, string roleName)
        {
            RoleManager roleManager = RoleManager.GetManager();

            if (roleManager.GetRoles().Where(r => r.Name == roleName).FirstOrDefault() == null)
            {
                roleManager.CreateRole(newId, roleName);
            }
            else
            {
                // Handle appropriately when the role already exists
            }

            roleManager.SaveChanges();
        }

    }
}

2. Manually synchronize the permissions at the production environment by navigating to Administration -> Permissions -> select 'by Role' tab and compare the settings for each role with the ones from Staging.