code: public ApiResponse<ApiSuccessResponse> sendCustomNotificationWithHttpInfo(String id, CustomNotificationData customNotificationData) throws ApiException {
          com.squareup.okhttp.Call call = sendCustomNotificationValidateBeforeCall(id, customNotificationData, null, null);
          Type localVarReturnType = new TypeToken<ApiSuccessResponse>(){}.getType();
          return apiClient.execute(call, localVarReturnType);
      }
docs: Send a custom notification
  Send a custom notification to the specified chat. The notification is typically used as a trigger for some custom behavior on the recipient&#39;s end.
  @param id The ID of the chat interaction. (required)
  @param customNotificationData Request parameters. (optional)
  @return ApiResponse&lt;ApiSuccessResponse&gt;
  @throws ApiException If fail to call the API, e.g. server error or cannot deserialize the response body