1. Unplug the power cord from the back of the monitor and the wall.
2. Hold the power button down for at least one minute.
3. Plug the power cord back into the monitor and then into the wall outlet.
4. Press the Menu button on the monitor.
5. Navigate to the Factory Reset option and select it.
6. Try a different cable connecting your monitor to your computer.
If the issue still persists, I'd suggest you Contact HP in your region regarding the service options for your monitor.
Hope this helps! Keep me posted.
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Asmita I am an HP Employee
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