This is using wrong sitemap, how to fix?

Hi Laura,
Apologies for not patrolling the free forum more diligently. This appears to be a plugin clash, between us and yoast. The plugin we generate is the sitemap generated by WP out of the box. We believe yoast is generating their own. We will look into a solution for this.

Okay, so what we know so far is 3 things:
1. Yoast over-rides the out of the box WordPress sitemap with their own.
2. You need to be running version WP 5.5 for that sitemap to be available
3. Not all hosting companies, the place you store your website on support the SimpleXML PHP extension that powers the sitemap.

We are continuing to do research, but please feel free to reach out to us via email.

Zuda,
Yoast actually provided a fix via htaccess for Apache users and it worked like a dream:

# Yoast SEO - XML Sitemap Rewrite Fix

RewriteEngine On
RewriteBase /
RewriteRule ^sitemap_index.xml$ /index.php?sitemap=1 [L]
RewriteRule ^locations.kml$ /index.php?sitemap=wpseo_local_kml [L]
RewriteRule ^geo_sitemap.xml$ /index.php?sitemap=geo [L]
RewriteRule ^([^/]+?)-sitemap([0-9]+)?.xml$ /index.php?sitemap=$1&sitemap_n=$2 [L]
RewriteRule ^([a-z]+)?-?sitemap.xsl$ /index.php?yoast-sitemap-xsl=$1 [L]
# END Yoast SEO - XML Sitemap Rewrite Fix

If you’re running it in a subfolder:

	# WordPress SEO - XML Sitemap Rewrite Fix - for subfolder install
	RewriteEngine On
	RewriteBase /wordpress/
	RewriteRule ^sitemap_index.xml$ /wordpress/index.php?sitemap=1 [L]
	RewriteRule ^locations.kml$ /wordpress/index.php?sitemap=wpseo_local_kml [L]
	RewriteRule ^geo_sitemap.xml$ /wordpress/index.php?sitemap=wpseo_local [L]
	RewriteRule ^([^/]+?)-sitemap([0-9]+)?.xml$ /wordpress/index.php?sitemap=$1&sitemap_n=$2 [L]
	# END WordPress SEO - XML Sitemap Rewrite Fix

That was awesome of them. What features would you like to see in upcoming updates of our plugin? We’re very sorry we didn’t catch this sooner.

So, after looking at their fix, it appears the problem wasn’t with our plugin, rather with WordPress being in a subfolder, which does cause problems. Nonetheless, we are here to help.