Duplicate URLs and missing pages in XML sitemap

We have two main issues in the sitemaps generated by Yoast:

• The same URL is repeated multiple times (up to 8 times). You can see this happen multiple times in https://www.mcafee.com/blogs/post-sitemap5.xml
• We’re missing over 2,300 articles in the XML sitemap, including whole languages as the Italian version of the blog.

From the pages that are indexed, some are in the sitemap, and some not. Example:

• In sitemap: https://www.mcafee.com/blogs/es-mx/family-safety/9-tipos-de-hackers-y-sus-motivaciones/
• Not in sitemap:?https://www.mcafee.com/blogs/es-mx/family-safety/que-pueden-hacer-los-padres-no-mas-brechas-de-proteccion-entre-tu-y-tus-hijos/

(We have a known issue where canonicals have an extra slash, but that doesn’t seem to be the cause as also the URLs in the XML sitemap have the extra slash in the canonical)

What we’ve done so far:

• Deactivated and activated the plugin
• Finished the first-time installation settings of Yoast
• Switched off the Yoast sitemap, pressed Save, and then activated it again
• Compared the source code of two pages listed above, but don’t see differences that could lead to the XML exclusion
• Checked whether the post content types are set to be shown in the search results in other languages, which is the case
• Compared the on-page Yoast settings between the two pages, one in the sitemap and the other not, but no difference in settings
• Checked the?common Yoast XML sitemap errors?and saved the Permalinks settings
• Flushed caching
• Tested if I deleted some old pages if the sitemap gets updated, which is the case. Also, see that some new pages have been added.

Could you please check why these issues are happening and how to resolve?

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