BB Z10 cannot Verify BBID from phone

[I posted this before signing in so am not sure if that would be accepted. This is an identical post (minus this message) -pardon any confusion.]

Any Settings function at all that requires Verify, from BBID itself to BB Protect, Set up Payment Options, etc., or any app that requires BBID such as BBW, etc., pulls up the Verify screen with keyboard. When I enter my password the keyboard disappears and it `thinks' for a short while then thrown up the keyboard again for another try. It is never accepted. In the case of the Settings/BBID function itself I only see the BBID status screen when I cancel the Verify request.

There is a persistent Notice in the Hub:
BlackBerry ID
One or more applications/services require you to verify your BlackBerry ID.

On the other hand, if I go to BBW on the web with a computer and choose an app to download, BBW will call the web-based BBID to identify me (my phone) and I can enter my BBID and then almost instantly the BBW app on the phone will open with the app I chose ready to download. When I try to download, however, it asks my to Verify and I am back to the same block. This shows that the web-based BBID can communicate with my phone.

Downloading and installing Amazon-located apps (using the phone's pre-installed Amazon store App for this) is no problem.

I can go to BlackBerry Protect on the web with a computer and log in with my BBID credentials, but the Locate service cannot find the phone. It was originally able to, until in early February. GPS-based apps work fine.

I went through BlackBerry Support Forums and they ended up saying they had no idea what was wrong. This Forum is now closed but the Forum history is still there; I kept a transcript in any case. I then went to BlackBerry Twitter Support and they could not solve it, saying I had to go to Telephone Support.

This phone was bought in January 2017 and so is still under warranty. I got it unlocked a couple of weeks after I bought it. It makes call, connects to the internet via Wi-Fi, Texts and does BB PIN messages no problem.

My retailer (large electronics department of a store that competes directly with large electronics stores) said the problem looks like the BlackBerry server.

BlackBerry Link will show the phone and identify it with right number and I can find it with Win 10 explorer and copy files to it and the 32Gb storage media I added but it won't do a Backup.

BB Link "Home" screen shows (from Screen capture from a few days ago):
BlackBerry-nnnn
BlackBerry Z10 (PINnnn)
Software release 10.3.3.1463
OS Version 10.3.3.2205
Last Backup Today 1:14 PM (which didn't work)
...and the colour-coded % storage of different file types.

But it also says "This BlackBerry ID isn't associated with a device running BlackBerry 10 OS, or there was an error processing our information"....(etc)