I've started a new website with a free domain name (.ga) from Freenom. When I tried to add my website to Google Search Console, the verification went well, but when I submitted the sitemap I get an error "couldn't fetch."
I've waited 2 days now but nothing changed. Does this mean that Freenom domains aren't allowed?
I also made a new website with the same template in the same host but without Freenom domains and submitted the sitemap XML and it got approved immediately.
.ga domains are allowed in Google Search Console. The failure to fetch your XML sitemap is not caused by the top level domain.
Submitting an XML sitemap to Google Search Console is usually not necessary and your site should do fine with SEO even if Google can't fetch the sitemap. XML sitemaps let Google know about all the pages on your site, but they don't help your site get indexed or ranked better. Whether or not you have submitted an XML sitemap, Googlebot will find and crawl your site. If you have linked every page from some other page, Googlebot will use those links to crawl your entire site even without an XML sitemap. If you haven't linked to every page, you should do so. Links to pages help Google decide to index pages and help rankings way more than XML sitemaps do.
To diagnose why Google can't fetch your XML sitemap you should:
If you find a problem with the above steps, correct it. Problems that can cause this error are:
However, Google is known to show this error fairly commonly because of problems on their end. Maybe their internet connection is flaky, or maybe there is a bug in their sitemap fetching code. We don't really know. In any case, if there are no problems on your end, the error will likely go away on its own within a few weeks. It is Google's fault often enough that a hosting company, Wix, has it in their FAQ: https://support.wix.com/en/article/google-search-console-couldnt-fetch-error
