Check to see if you have any sync error logs.

Type about:sync-log in the Location Bar and hit Enter.

Then view the log and see if you can find the error. Or you can paste the sections of the report in pieces in the Post a Reply here in succession and someone who is familiar with sync logs can look for the issue / problem. This forum won't handle a full error log, so multiple Replies are often necessary. Plus the formatting of wide text files here makes it hard to read. Not very user-friendly for copy'n'paste sections of text. Unless you have a "pastebin" site you are comfortable using; then paste the log there and hyperlink to that posting.

It works good today. I try to log in after seeing this article and I get an email confirm code, now it can syncs again!

Thanks everyone!!

Hi, I'm trying to sync pc to laptop. I downloaded the app to my android and when going to sign in they say my password must be 8 numbers but my current password is only 6. How can I sign in to sync? Thank you

hello, i got the same problem after i reinstalled windows. my laptop and phone seems to be able to keep on syncing, but my desktop on a fresh install just gives me the error message.

https://pastebin.com/Tf0wTPpB

theres the latest log

thanks in advance.