Bookmarks missing from sync

Brave browser installed on Pixel 3XL with Android 10, fully patched.
Brave browser installed in Windows 10 laptop, version 1909.
Brave Version: 1.5.1 on Android and 1.0.1 on Windows.

I created a sync chain, both devices show up when I check the sync menu on each.
On the mobile device, less than half the bookmarks synced. I waited 24 hours, no further bookmarks showed up.
When I check the Windows laptop, all the bookmarks imported from Chrome are there.
If there a manual way to import bookmarks? A way to force a sync manually?
What have I done wrong?

-Mike

I left the sync chain and removed both devices (Windows laptop and Android smartphone), then started a new sync.
It took about 5-6 hours, but finally all the bookmarks from my laptop synced to the smartphone.

-Mike