How to Post an agreement with transientDocumentId

[ramk21831647]

i'm getting a transientDocumentId from   transientDocuments method .

After that posting agreement using above  transientDocumentId .

i'm getting this error.

{
  "message": "The Library Document ID specified is invalid",
  "code": "INVALID_LIBRARYDOCUMENT_ID"
}

how can i get the valid Library Document ID.