my iPhone 6 iOS 9.02 says switched off when someone calling me even my phone is on

Hello, Basil Sulthan Bathery.

Thank you for visiting Apple Support Communities.

It sounds like you are not receiving phone calls even if your device is on. I would need a little clarification on what you mean by switched off to provide a better answer. However, here are a couple resources that may help resolve this issue.

If you can't make or receive calls on your iPhone

Use Do Not Disturb on your iPhone, iPad, or iPod touch

Cheers