how to fix [Error]CoreMediaErrorDomain error -42681 ?

i am using DRM content in my player. facing this error frequently . we used both licenseUrl ,certificateUrl and DRM token .Content is not playing getting this error .

The FairPlay Streaming Programming Guide that comes with the FairPlay Streaming Server SDK contains a description for error code -42681. Please check that your SPC messages contain the correct version. Please also refer to Debugging FairPlay Streaming for instructions on how to verify your KSM implementation.

how to fix [Error]CoreMediaErrorDomain error -42681 ?
 
 
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