Airplane Mode Greyed Out

Airplane mode is greyed out and i already tried everything i could but no effect on it.

These are the things that i tried:

1. Through "change PC settings'' option.

2. Using Airplane mode on/off key.

3. Updating Airplane Mode Switch Driver (it was already updated).

I also tried a method that i found in a forum which was ''Device Manager-->Network Adapters--> Under that Right click your network adapter-->Properties-->Power Management-->unchecking the "allow the computer to turn off this device to save power'' option.

My Laptop model is  Dell Inspiron 15(3542)