Additional Backup Storage Discontinued?

I am using Norton Security on 8 devices (of the 10 I'm licensed for).  On two large Windows PCs, I use the cloud backup functionality.  I far exceed the storage that comes with the product, and I have to buy additional storage.

(Unrelated, I also use external hard disks for a separate backup, but I also want the cloud backups.)

I've been approaching my max and the Norton client has been bugging me to buy more storage.  I last bought some in March.  Since then, although the product is still bugging me, it won't let me buy more. When I click on the link in the product, it won't open a browser.  I've tried multiple browsers, disabling ad blockers/popup blockers, tried multiple PCs, Live Update, and done a Norton delete/reinstall.  Nothing worked.

I opened a support chat window today.  The support person told me that that the additional backup option is "obsolete."  (If that's the case, then why does the product keep prompting me to buy it??)  I've seen no reference to this online.

He then pitched the same Norton 360 Premium upgrade that Norton emailed me about last week.  Problem is, that's still not nearly enough storage, and if I can't buy more, that doesn't help me.  I don't need the additional features of 360.

Can anyone confirm whether the additional storage product has been discontinued?

If it has, I'll need to look for a different cloud backup service... and Norton will lose the revenue from my buying the extra storage.

If the product hasn't been discontinued, does anyone have any suggestions on how to remedy my problem?  I'm afraid if I open another support case, I'll just get the same runaround.