Hi Laila,
Since the URLs are different, each one is counted as one install. There are some URLs that don’t count – you can read more about how this works here. If you recently changed the URL or migrated the site, that is likely the reason that you are seeing the message. If you want to use the key on ssbad.dk, then you will need to deregister blaakjaertesting.dk.linux16.curanetserver.dk by following the instructions here. This is not something that I am able to do from my end. However, once you deregister the key from blaakjaertesting.dk.linux16.curanetserver.dk, you should no longer see the message on ssbad.dk.
Can you give this a try and let me know if it works for you?
Thanks,
Jennifer