Camera flickering

shutter speed value could not be adjusted on this camera.
So I tried modifying the exposure value, but it doesn’t solve the problem.

here is my code

#include <iostream>
#include <ctime>
#include <libobsensor/ObSensor.hpp>
#include <opencv2/opencv.hpp>

#include "libobsensor/hpp/Pipeline.hpp"
#include "libobsensor/hpp/Error.hpp"
#include <thread>

using std::cout;
using std::endl;

int main(int argc, char **argv) try {
    // Create a pipeline with default device
    ob::Pipeline pipe;

    // Configure which streams to enable or disable for the Pipeline by creating a Config
    std::shared_ptr<ob::Config> config = std::make_shared<ob::Config>();
    std::shared_ptr<ob::VideoStreamProfile> colorProfile = nullptr;
    try {
        auto colorProfiles = pipe.getStreamProfileList(OB_SENSOR_COLOR);
        colorProfile  = colorProfiles->getVideoStreamProfile(640, 480, OB_FORMAT_RGB, 30);
        config->enableStream(colorProfile->as<ob::VideoStreamProfile>());
    }
    catch(...) {
        std::cout << "color stream not found!" << std::endl;
    }

    try {
        auto depthProfiles = pipe.getStreamProfileList(OB_SENSOR_DEPTH);
        auto depthProfile  = depthProfiles->getVideoStreamProfile(640, 480, OB_FORMAT_Y12, 30);
        config->enableStream(depthProfile->as<ob::VideoStreamProfile>());
    }
    catch(...) {
        std::cout << "depth stream not found!" << std::endl;
    }

    try {
        auto irProfiles = pipe.getStreamProfileList(OB_SENSOR_IR);
        auto irProfile  = irProfiles->getVideoStreamProfile(640, 480, OB_FORMAT_ANY, 30);
        config->enableStream(irProfile->as<ob::VideoStreamProfile>());
    }
    catch(...) {
        std::cout << "ir stream not found!" << std::endl;
    }

    // Configure the alignment mode as hardware D2C alignment
    config->setAlignMode(ALIGN_D2C_HW_MODE);

    try {
        pipe.start(config);
    }
    catch (ob::Error& e) {
        std::cerr << "function:" << e.getName() << "\nargs:" << e.getArgs() << "\nmessage:" << e.getMessage() << "\ntype:" << e.getExceptionType() << std::endl;
    }

    auto dev = pipe.getDevice();

    dev->setIntProperty(OB_PROP_COLOR_BRIGHTNESS_INT, 0);
    dev->setIntProperty(OB_PROP_COLOR_CONTRAST_INT, 25);
    dev->setIntProperty(OB_PROP_COLOR_SATURATION_INT, 70);
    //dev->setIntProperty(OB_PROP_COLOR_HUE_INT, 40);
    dev->setIntProperty(OB_PROP_COLOR_GAMMA_INT, 72);
    dev->setIntProperty(OB_PROP_COLOR_GAIN_INT, 0);
    dev->setIntProperty(OB_PROP_COLOR_SHARPNESS_INT, 6);

    dev->setIntProperty(OB_PROP_COLOR_POWER_LINE_FREQUENCY_INT, 2);

    dev->setBoolProperty(OB_PROP_COLOR_AUTO_EXPOSURE_BOOL, false);
    dev->setIntProperty(OB_PROP_COLOR_EXPOSURE_INT, 20);

    clock_t past;
    int key;
    cv::Mat colorMat, depthMat, dstMat = cv::Mat(640*2, 480, CV_8UC3);

    while(true) {
        past = clock();

        auto frameSet = pipe.waitForFrames(100);
        if (frameSet == nullptr) {
            continue;
        }

        auto colorFrame = frameSet->colorFrame();
        auto depthFrame = frameSet->depthFrame();

        if (colorFrame != nullptr && depthFrame != nullptr) {
            colorMat = cv::Mat(colorFrame->height(), colorFrame->width(), CV_8UC3, colorFrame->data());
            cv::cvtColor(colorMat, colorMat, cv::COLOR_RGB2BGR);

            depthMat = cv::Mat(depthFrame->height(), depthFrame->width(), CV_16UC1, depthFrame->data());
            cv::normalize(depthMat, depthMat, 0, 255, cv::NORM_MINMAX, CV_8UC1);
            cv::cvtColor(depthMat, depthMat, cv::COLOR_GRAY2BGR);
            
            cv::hconcat(colorMat, depthMat, dstMat);
            cv::imshow("dst", dstMat);
        }

        //cout << clock() - past << endl;
        key = cv::waitKey(33);
        if (key == 'C' || key == 'c' || key == 'Q' || key == 'q') break;
    }
    pipe.stop();
    return 0;
}
catch(ob::Error &e) {
    std::cerr << "function:" << e.getName() << "\nargs:" << e.getArgs() << "\nmessage:" << e.getMessage() << "\ntype:" << e.getExceptionType() << std::endl;
    exit(EXIT_FAILURE);
}

I know. Why are you talking about useless things? I would like to solve the problem of horizontal lines appearing.