page-sitemap.xml / post-sitemap.xml – HTTP 403 error (Forbidden)

Hi guys,
I cant get my head around this.
Im only using the site map for pages and posts:
page-sitemap.xml
post-sitemap.xml

and although my Google webmaster recognize the main site map page:
index-sitemap.xml

it seems to be blocked for all the rest:
page-sitemap.xml – HTTP 403 error (Forbidden)
post-sitemap.xml – HTTP 403 error (Forbidden)

the top of my htaccess i have tried with both extra codes to resolve the issue (but with no luck):

# Yoast SEO - XML Sitemap 403 Fix
<FilesMatch "(sitemap_index.xml|page-sitemap.xml|post-sitemap.xml)">
	allow from all
</FilesMatch>
# END Yoast SEO - XML Sitemap 403 Fix
# WordPress 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?xsl=$1 [L]
# END WordPress SEO - XML Sitemap Rewrite Fix

When trying to fetch as Google i get an Error. and when looking at the code, strangely enough i can at the header a “X-Robots-Tag: noindex, follow”

Any idea why is that, or why is that showing?

https://wordpress.org/plugins/wordpress-seo/