Library of Congress codes

I apologize if I'm being stupid. In the past, when I entered a LOC number eg. "38-15724", using the LOC radio button, I would get a result back. Recently, when I enter a number, I get a message "No results found for '38015724'", with the dash replaced by a 0. Has something changed that I don't know about?
Please advise.

There's an open bug about Library of Congress, could your problem be related to this?

https://www.librarything.com/topic/328620