The site in reference is a client site and I do not want to mention it, so I'll use the made up FooBar for this example.
The other day, if you searched for
FooBar Google would show you the website for
foobar.com as the first result. Now, if you search
FooBar Google asks: "Did you mean foo bar?" and doesn't show any results.
I know the site is still indexed because if I search for "FooBar" (with quotes) I see it, plus a lot of other results for the site.
The day before I submitted a sitemap.xml file and since then it's borked. According to Google Webmaster Tools there's nothing wrong with the sitemap, and there are no errors on the site; it's clean and is performing well.
Why did this happen and how to I fix it?
Edit: this site has been online for almost a year, so it's not like Google doesn't know about it.