1. Please restart both the monitor and the computer to see if the screen returns to normal;
2. Please check if the signal cable is damaged, try reconnecting or replacing the cable to see if the issue is resolved;
3. Please check if the monitor's resolution and refresh rate settings are correct;
4. Please try connecting the monitor to another device to see if the screen functions properly;
5. Please try updating the graphics card driver to see if the screen returns to normal;
6. If none of the above methods solve the issue, please contact customer support for further diagnosis and repair.