Hi,
As per the query you are trying to set the monitors to sleep after 10 min of inactivity and after 10 min you see all the application were on the main/primary monitor.
Please provide us the below information.
1. What is the make and model of your Computer?
2. Which windows 10 build are you using?
3. Do you get any specific error code?
The issue might be occurring due to corrupted display drivers.
Lets update the display drivers :
1. Press Windows key + R, to open the run command.2. Type "devmgmt.msc" and press enter to open device manager.
3. Expand "display adapter".
4. Right-click on the driver and click on Update Driver Software.
5. Your computer should find and automatically install the updated driver.
6. After the installation is complete, Restart your computer.
Keep us informed with the status of the issue.
We are here are to assist you.
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