code: @Delete("json")
  	public final void deleteDeviceRegistrationRequest(final Representation entity) {
  		Request request = getRequest();
  		Map<String, Object> requestAttributes = request.getAttributes();
  		String deviceLibraryIdentifier = (String) requestAttributes.get("deviceLibraryIdentifier");
  		String passTypeIdentifier = (String) requestAttributes.get("passTypeIdentifier");
  		String serialNumber = (String) requestAttributes.get("serialNumber");
  		ChallengeResponse authString = request.getChallengeResponse();
  
  		LOGGER.debug("deleteDeviceRegistrationRequest - deviceLibraryIdentifier: {}", deviceLibraryIdentifier);
  		LOGGER.debug("deleteDeviceRegistrationRequest - passTypeIdentifier: {}", passTypeIdentifier);
  		LOGGER.debug("deleteDeviceRegistrationRequest - serialNumber: {}", serialNumber);
  		LOGGER.debug("deleteDeviceRegistrationRequest - authString: {}", authString);
  
  		Status responseStatus;
  		try {
  			responseStatus = handleUnregisterDeviceRequest(deviceLibraryIdentifier, passTypeIdentifier, serialNumber, authString);
  		} catch (PKAuthTokenNotValidException e) {
  			responseStatus = Status.CLIENT_ERROR_UNAUTHORIZED;
  		}
  		setStatusIntoResponse(responseStatus, getResponse());
  	}
docs: /*
  DELETE request to webServiceURL/version/devices/{deviceLibraryIdentifier}/registrations/{passTypeIdentifier}/{serialNumber}