download does not complete

The download does not complete. This is first time downloading this 3.5.6 software and am getting a message from windows: digital signature does not match.
What is digital signature?
How do I correct this problem during download?

are you downloading the installer directly from LibreOffice or are you using the torrent file? If you are not using the torrent that would be my recommendation to get around this issue. As for the digital signature, I think I understand what it is but do not know how to explain it. Additionally are you downloading directly from https://www.libreoffice.org/download/ or some other site?