Hello,
Thanks for contacting us and sorry for any inconvenience that might have been caused due to that.
I checked your sitemap with XML Validator and it is working fine:
Please remove all previously submitted sitemaps from your GSC account and resubmit your main sitemap. Wait for Google to crawl and that should resolve the issue.
As for the URL, the error is a 5xx server error that can be resolved by your hosting provider. If they are saying that everything is working fine from their end then you can try validating the fix for the affected URL and check if Google is able to crawl it or not.
If the issue persists then get in touch with your host again and ask them to look into this again.
Hope this helps. Let us know if you need any further assistance.
Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.