Sub Domain Sitemaps

Hi!

We have a good amount of subdomains that we are trying to create sitemaps for, however every time we build the sitemap it adds links from our other subdomain. We need it to only have the pages associated with the subdomain its on. Also it adds the pages as links and not pages, and when we try to hit the edit button we get this error: There are currently no XML sitemap contexts available. Please help!

Thanks,
Renee