Edit your robots.txt file to allow robots the access to your sitemap.
Where is the default folder location for this?
It doesn’t appear to exist :/
If it is manually added, it shoud be in the root directory of your blog.
Else, if it is dynamically generated by WordPress, check if there’s actually a block present in the file by going to – YourDomain.com/robots.txt
Replace YourDomain with your actual domain name.
It’s not there – should I create one?
You don’t need to, if you are not looking to add specific blocks.
Just check in your Dashboard> Settings> Reading that the box in front of Discourage search engines from indexing this site is unchecked. If it is checked, un-check it and save the changes.
Strange! What text shows up when you open YourDomain.com/robots.txt
Certainly a plugin is doing that change to your dynamic robots file.