The screen is unresponsive when tapped (touch function failure)?

Check Cables: Verify whether the internal or external USB touch cables and serial cables within the advertising display unit are loose or disconnected. 

Power Supply: Some large-format touch frames require an independent power source; check to ensure the power adapter is securely plugged in. 

Driver Issues: Restart the device, or check the Device Manager in the system backend to verify that the touch driver is functioning correctly.