There doesn't seem to be much response to anything 'Notes' related. I'll answer myself and maybe it'll be of some help to someone. I actually really rely on the 'Notes' app.
After a total nightmare of trying to re-set-up my iCloud mail accounts. it appears that my mac had locked me out of iCloud. I could log into iCloud on the iCloud.com website but my Mac couldn't and maybe after several attempts at setting up my iCloud 'Mail' accounts, it must've locked me out as I got 'the attached' message... 'wait several days' message. Clicking 'Continue' didn't work. I gave my Apple ID email address to confirm my identity, no email came. I chose the option of entering the day and month of my birthday. It told me the info didn't match their records.
No matter what I did, try numerous passwords, generate numerous app-specific password, nothing worked and no clear message as to what to do. Sometimes I would add my user email and password, that I knew to be correct and it would suggest that I was logged in by just clearing the log-in window. No confirmation or anything! No suggestion that I'd done this too many times!
After a couple of days or so, from 'System Preferences' > iCloud, I had another attempt at logging in. This time, out of the blue I got another window, prompting me to choose what I wanted to sync. I clicked 'Notes' (amongst others), and voila! everything synced.
To a not very iCloud-savvy man like myself, it was all a bit confusing. Way too many user and passwords. Get one wrong and Bamm!
So the moral to this story, you may just have to wait 'several days' to log onto iCloud on your device. Punishment for trying too many passwords? I don't know.
I hope this helps.
