code: public FactorEnrollmentResponse activateFactor(long userId, long deviceId) throws OAuthSystemException, OAuthProblemException, URISyntaxException
      {
      	cleanError();
  		prepareToken();
  
  		URIBuilder url = new URIBuilder(settings.getURL(Constants.ACTIVATE_FACTOR_URL, userId, deviceId));
  
  		OneloginURLConnectionClient httpClient = new OneloginURLConnectionClient();
  		OAuthClient oAuthClient = new OAuthClient(httpClient);
  		OAuthClientRequest bearerRequest = new OAuthBearerClientRequest(url.toString())
  			.buildHeaderMessage();
  
  		Map<String, String> headers = getAuthorizedHeader();
  		bearerRequest.setHeaders(headers);
  
  		FactorEnrollmentResponse factorEntollmentResponse = null;
  		OneloginOAuthJSONResourceResponse oAuthResponse = oAuthClient.resource(bearerRequest, OAuth.HttpMethod.POST, OneloginOAuthJSONResourceResponse.class);
  		if (oAuthResponse.getResponseCode() == 200) {
  			JSONObject data = oAuthResponse.getData();
  			factorEntollmentResponse = new FactorEnrollmentResponse(data);
  		} else {
  			error = oAuthResponse.getError();
  			errorDescription = oAuthResponse.getErrorDescription();
  		}
  
  		return factorEntollmentResponse;    	
      }
docs: Triggers an SMS or Push notification containing a One-Time Password (OTP)
  that can be used to authenticate a user with the Verify Factor call.
  
  @param userId
  The id of the user.
  @param deviceId
  the id of the MFA device.
  
  @return FactorEnrollmentResponse Info with User Id, Device Id, and OTP Device
  
  @throws OAuthSystemException - if there is a IOException reading parameters of the httpURLConnection
  @throws OAuthProblemException - if there are errors validating the OneloginOAuthJSONResourceResponse and throwOAuthProblemException is enabled
  @throws URISyntaxException - if there is an error when generating the target URL at the URIBuilder constructor
  
  @see <a target="_blank" href="https://developers.onelogin.com/api-docs/1/multi-factor-authentication/activate-factor">Activate an Authentication Factor documentation</a>