[Plugin: WordPress SEO by Yoast] Sitemap errors

When I go to Google Webmaster Tools I get an error under the /feed. It says Issue: invalid xml: too many tags.

Description: too many tags describing this tag. Please fix it and resubmit. Issues count: 15.

Example: Parent Tag: channel, Tag: feedFlare, Line: 14

Any ideas what’s going on and how to fix it?

Thanks.

https://www.ads-software.com/extend/plugins/wordpress-seo/