Restricted error while compressing PDF

Hi,
Getting an error while compressing a document. The error message says,

com.adobe.pdfservices.operation.exception.ServiceApiException: description ='Source file cannot be processed because of some restrictions.; requestId=1daea1a6-.......................'; requestTrackingId='1daea1a6-2e7b-...............'; statusCode=400; errorCode=DOCUMENT_RESTRICTED

I removed requestTrackingId, requestId values and replaced with .............. due to privacy.

Could someone please help me why is it throwing error?