I myself was experiencing this same issue, but after a lot of research I found out that the problem is in the Microsoft Windows itself whether it's 7 or 10 etc. because it doesn't recognize the setting correctly when sleep mode is set to "Never"
But don't worry I have found a unique solution for it that's why I made this post.(Read it full)
1) Go to Control Panel and click on Power Settings.
2) Click on Change Plan Settings and from there select Advanced Power Settings.
3) Then Select Sleep Option and expand it
4) From there select option "sleep after" and for both "On battery" and "Plugged in" enter a very large value for example, 14400.
NOTE: PLEASE MAKE SURE that "On battery" and "Plugged in" value is NOT SET TO "NEVER". The reason I told you in the start.
CONCLUSION: Basically, we are fooling Windows now that you can sleep, but after 14400 minutes are over and definitely it won't happen in reality. Also, It's a shame for the Microsoft that this issue was due to them and we have to figure other workaround like this.