On the #fortinet #fortimanager vulnerability (CVE-2024-47575), one remediation step is to set disallow new Fortigates from registering automatically, the default setting. Be aware, if you don't have a #Fortigate in the device list already registered, you will not be able to add it even with a cert. To ensure all of your firewalls are in the device list in FortiManager:

diag dvm device list.

There are other remediations you can do, but if you use this one, look at your device list first.