New and old phone (without sim) both ring when receiving a call!

[Al2]

I bought a new iphone sim free and have put my SIM card into this. I have given the old device to my mother, who just uses that old phone to connect to the internet without inserting her SIM card. However when somebody calls me BOTH my new phone with sim and my old phone without any sim ring! How is this happening?! And more pressingly how do I stop it? Any help much appreciated.

[gmarkj · Accepted solution]

Sounds like the old phone still has your number in the settings.
It is under settings > my phone > my number.
Change this, hit save and reboot phone.
Should fix the issue.
You might also want to check whether your Apple id is logged in on the old phone too...

[MI5]

@Al2 

You need to sign out of your Apple ID on old phone.