Troubleshooting Tip : 'Failed to add FortiSASE service' error in FortiManager

[btey]

Description	This article describes the issue when adding a FortiSASE instance on FortiManager, the error 'Failed to add SASE service: Failed to add service' appears.
Scope	FortiSASE, Advanced NFR license, FortiManager, v7.4.6.
Solution	To check the details of the error using the commands below in FortiManager: diagnose debug application dmsase 255 diagnose debug enable Error display showing unsupported device os type: Response [unknown]: { "id": 224, "result": [{ "status": { "code": -20024, "message": "Unsupported device os type"}, "url": "dvm\/cmd\/add\/device"}]} Advanced NFR license with S/N FEMSAN is currently not supported in FortiManager v7.4.6 and will be included in the upcoming v7.6.4.