There is a problem in the SEO section in the tag configuration.
Setting index/follow in the Meta robots index section: to a tag does not enable the Page Title option to introduce an SEO title, nor does the tag with index/follow be added to the Sitemap.
Another thing that happens is that if in the Site Settings / SEO / Tags page you set it as index/follow and then on the tags page you set the tags as noindex/follow in the SEO section, they continue to appear in the Sitemap.
apologies for my bad english, it is not my native language, a translator is my best friend in these cases.
