I am having the same difficulty.  On hold right now.

Lacerte Support suggested downloading the Lacerte Tool Hub, which I was told can force the update. Unfortunately, it would take an hour to download. The Lacerte rep said I had a slow connection. End of story. Really!!? No other help was offered.

Did you ever get this issue resolved.  My software is now doing the same thing.

Yes.  Turns out my modem, router and firewall all went bad.  So had to have it all replaced.  Have you tried unplugging your modem from the wall, wait about a minute, then plugging it back in, and trying again?  I have found that that works sometimes.

I would first try;

Press Windows Key and type 2021 Lacerte Web Setup

Select that to start the install process. This is generally much more reliable than the in product Update.

I was having the same issue, waited for a few minutes then canceled the update. Did that 2-3 times and the full update went through. Hope this helps!

Thank you for the help this worked for me as well.  Cancelled twice, third time the charm :).