Hello Mogamal,   We as moderators don't support the APIs and as a result, don't have a lot of experience with them. The community may be able to add more to this tread.   With that said this what I can find:   Check that you are on the latest iDRAC 5.00.00.00 firmware.   iDRAC9 Redfish API - SecureBoot section [URL]#/overview-doc/2978/6818/openapi.yaml/paths/~1redfish~1v1~1Systems~1{ComputerSystemId}~1SecureBoot~1Actions~1SecureBoot.ResetKeys/post   I hope this helps.  
Hello Community , Just need a support on how to import and configure SecureBoot Certificates using Redfish API on PowerEdge R740    Thank you 
Configure R740 SecureBoot Certificates using Redfish