change frequency and priorities differ from ones at settings

Hi! I’ve read FAQ and forum but have not found a similar topic, sorry if I’ve missed it. I use the last version of WordPress and the 4.0.9 version of the plugin, my website is https://flower-garden-design.com/. The issue is that I set up the categories as ‘90%’ and ‘weekly’ but the sitemap shows them as 0% and ‘never’: https://flower-garden-design.com/sitemap-tax-category.xml. I saved the settings and checked several times before asking.

I use also FV Simpler Seo and Robots Meta plugins; and the categories are NOT prevented from indexing by these plugins.

What should I do to fix this strange problem? Thanks in advance!

https://www.ads-software.com/plugins/google-sitemap-generator/