We're using Jira and Confluence, both the cloud versions and also bitbucket for development of some projects.
I'm creating a "Software project space" within Confluence to link to a JIRA project that I've just created successfully. I've picked the newly created project name from the list and all the fields have been populated including the Space key, which it's defaulted to the same key as the project. All required fields are filled out, however, the Create button is still "greyed" out, and so I can't create the space.
Creating a blank space doesn't have this issue, but I haven't followed through as I don't want to burn the space key.