SANtricity System Manager REST API call for iSCSI interface fails with 422 Error

• Error observed issuing API call to disable iPv6 on all host side iSCSI ports:
  • In SANtricity System Manager > Help > API Documentation > POST > /storage-systems/{system-id}/iscsi/interfaces/{id} 

curl -X POST "https://<array_name>/devmgr/v2/storage-systems/1/iscsi/interfaces/1101010000000000000000000000000000000000" -H "accept: application/json" -H  "Content-Type: application/json" -d "{  \"ipv6Enabled\": \"false\"}"

422 Error:
{
  "errorMessage": "The updated object named ''{0}'' could not be found.",
  "developerMessage": null,
  "localizedMessage": "The updated object named '1101010000000000000000000000000000000000' could not be found.",
  "retcode": "updatedObjectNotFound",
  "codeType": "devicemgrerror",
  "invalidFieldsIfKnown": null
}

• The output of GET> /storage-systems/{system-id}/iscsi/interfaces/{id} shows that the interfaceRef is valid:

curl -X GET "https://<array_name>/devmgr/v2/storage-systems/1/interfaces?interfaceType=iscsi&channelType=hostside" -H "accept: application/json"

   "interfaceRef": "1101010000000000000000000000000000000000",
        "ipv6Enabled": true,