XML Sitemap not working

Hi there,

I enjoy the plugin very much but I have a problem with creating XML Sitemap. Each time when I generate the sitemap and then when I want to check it there is an error

Catchable fatal error: Object of class stdClass could not be converted to string in /homepages/40/d444244322/htdocs/mysite.com/wp-includes/taxonomy.php on line 813

I don’t know how to solve the issue, I have already updated WordPress and the plugin to the newest version, and also disabled all the plugins but it didn’t work. I am using wpml to translate the website so I would really need that function properly.

Could you please help me?

Thank you

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