Multisite, multidomain

hi, i’ve a probelm with multisite. I’ve a site with subdomain multisite.
es domain.com x.domain.com d.domain.com etc

I install yoast but it create sitemap for any subdomaind (domain.com/sitemap_index.xml, x.domain.com/sitemap_index.xml .

I think that isn’t correct, the site is really one con one theme.
How can resolve?

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