Duplicated sitemap for custom post type

Hello everybody,

I have the following issue with the sitemaps generated by the Yoast WordPress Seo plugin. If you check the sitemaps generated at https://chadel.byethost7.com/sitemap_index.xml you will notice that https://chadel.byethost7.com/offers-sitemap.xml appears twice and while it is linking to the same xml file it shows different date and time under “Last Modified”.

Anyone have an idea why this is occurring and perhaps a possible solution?

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