Not updating in LibreOffice

When I open LibreOffice, a message says that an update is available. When I click install, a window opens saying “Downloading Extension.” The green bar is all the way to the right, indicating that it has been downloaded. But then nothing happens.

I am using LibreOffice Version 5.4.2.2 (x64), Windows 10, and am trying to update from LT 3.8 to LT 3.9.