I am logged into my CC account and trying to activate a font. However, the font activation button is missing.
Sorry for the delay in response. If you're still experiencing the issue. Would you mind trying again to logout of Creative Cloud, restart the machine and then sign back in? If that doesn't help, please uninstall the Creative Cloud desktop app using this cleaner tool: https://helpx.adobe.com/in/creative-cloud/kb/cc-cleaner-tool-installation-problems.html and install it again.
Let us know if that helps.