How do I wipe out personal information to a lost windows phone? Bought Galaxy S 5 instead

[Windows Central Question]

Recently I had a Windows Nokia Lumina older phone. This phone is in else's name just using it until I could move to a state where my old carrier is useless. Now that I have a Samsung Galaxy S 5 phone the Windows phone won't come off my new cell phone. Worried about my personal and contact information getting into wrong hands. Thank you.

 

[michail71]

If you had a pin on there they would have to guess it or wipe the phone out before they could use it.