Custom posts not showing up in sitemap

Hi Support,

my custom posts are not showing up in de sitemap. => https://www.brixxs.com/ufaq-sitemap.xml
it shows empty

for example
https://www.brixxs.com/faq/wat-is-een-memoriaalboeking/
https://www.brixxs.com/faq/is-video-conferencing-veilig/
https://www.brixxs.com/faq/hoe-kan-je-videobellen-met-whatsapp/

in total i have right now about 70 custom posts which are not in the sitemap.

for this purpose i excluded the pages and posts from being in the sitemap, but these are working correct.

Also did save the permalinks again etc.
Excluded the sitemaps urls form being cached by another plugin, deactivated also the plugin.

What can i do to solve this?

Thank you in advance!

Ray