eLC serial number not unique??

Sorry to post this in the wrong forum, but it is the only one to which I can post a message (perhaps as I have been unable to register my software.)

I just bought a new UR824 and installed the eLicenser, but everytime I try to use it I get:

“Unfortunately, the serial number of your Soft-eLicenser is not unique.”

It happens at step 3 and 6 of Online Synchronisation & Maintenance, and also if I try to enter an activation code, or give my eLicenser serial number in MySteinberg.

It looks like the same problem as was reported here eLC serial number not unique?? - #2 by RokGeetar - Cubase - Steinberg Forums

This has meant that I am unable to submit the activation code for Rev-X etc. and unable to get a permanent license to use Cubase AI from the MySteinberg website.

I’ve tried submitting a support request, but it’s been over 48 hours and I have had no reply. This is my first Steinberg product, and my buying decision was based on Cubase AI being useable for my application. Sadly, if this can not be resolved, the product will have to be returned.

Has anyone already gone down this path and found the solution?

My system:
Acer aspire 5742 laptop with i3-370M processor
4Gb RAM. Windows 7 version 6.1 (build 7601: Service Pack 1)
eLC version 6.5.4.1116
Antivirus: AVG free edition 2013 (disabled)