Did you install and enable CBSubs Tax integration plugin (even with no tax rate set) ?

(CBSubs Tax integration plugin is required for CBSubs Promotion because of geo-zones in CBSubs 1.2)

Define a start and stop date instead of leaving blank and it should work.

That's a last minute regression bug while fixing a start/stop date bug of CBSubs 1.2 I just found.

Fixed for CBSubs 1.2.1:
#2597

Please confirm that by defining the start and stop date it now works.

At second thought, the other bug will probably not affect your own issue, as you probably have start and stop dates as coupon shows.

- Can you please try installing over the taxes integration plugin so we make sure all is installed correctly, publishing it in CB plugins management, make sure it's enabled (save config) in CBSubs Settings and try again ?

If it still doesn't work, then there is something with the invoicing address settings, and easiest would be to review your site settings and try to find from where that bug comes. In that case you can private-message me through my profile (make sure you are using https so information is encrypted) admin access information, so I can try to find why it works here and on our test sites, and not on yours ?

Thanks in advance, we want to solve your issue quickly.