Windows iCloud password app not populating passwords from iPhone

I installed the iCloud password app on my Windows 10 laptop. It works fine locally. But it’s not downloading my keychain passwords from my iPhone. Is there a special procedure I need to follow to accomplish this?

Have you set the keychain to be shared in iCloud on the phone? I just checked and it was disabled on my phone…

Thanks. I did check that, thanks.
I did get some help from an Apple Support tech and it sort of works. It’s a bit flaky though.