Hi, and welcome to Micro.blog! 
Did you make the changes recently? While DNS updates are usually pretty quick these days, in theory it can take many hours for the changes to fully propagate across the thousands of servers that make up the global DNS system.
Your screenshot looks good to me if your blog is hosted in the U.S. (You can choose to host it in the EU too.)
If you want support for the www subdomain, you’ll need to set up a CNAME record as well.