You can fix the problem of Sleep Mode of your System manually. Just follow the steps and let your System sleep when you are not using it.
The first thing you can do is to troubleshoot your power of the System.
Open control Panel and type Troubleshooting and open it. Then click on System and Security".
After opening “System and Security", you’ll see the option for “Power". Click it to open.
Now its troubleshooter window will open. Click on “Next" button to go ahead and see the results at the end of Troubleshooting.
After the few seconds, it will solve your problem related to the Power of System and let your System sleep after some time when your System is sitting idle.
If Any program is stopping the System from Sleep Mode
A program can also interfere in sleep mode. You can easily check it if any program is creating the hindrance.
Open the Command Prompt window with the Administrative privileges.
Run the following command: powercfg -requests
This command shows the list of processes which are in use and may prevent the computer from sleeping.
Now you can see, the executable process is chrome, and an “audio stream is in use". This means the program which is using audio stream is open on your System. As I am using Skype so this issue points to Skype software and says that Skype may prevent your System to go to Sleep Mode. Or Chrome browser can also be the reason of it as Chrome is also running on my System.
Close Chrome and Skype if they are running on your System. Then you can see that your System will go to sleep after some time when you left your machine idle.
There are other factors that may cause this sleeping problem but these two are the most common. These solutions can help even in troubleshooting other problems related to Power Options. I hope now you System will not stay awake all time and will go to sleep after a specific time interval. Feel free to ask anything related to it.