Hi,
I have similar problem at my 3 different wordfence which are already installed.
When i login to the wordpress dashboard at the top i saw a warning which says wordfence intallation uncomplete. For checking what is it? I press to continue button. Then licence window opens.
I tried to complete it with several times, with old licence key it didn’t work. Then get the new licence key and it didn’t work as well.
As a final, i checked the plugin list and saw there is a new version of wordfence which is 8.0.2
My installed versions are 8.0.1. not so oal but i made the update at one of the system.
And it starts to works.
Please try to update your wordfence to 8.0.2. I think it solves your problem.
Regards.