I want to set up iCloud keychain on my apple devices. To do so I went to settings > iCloud > keychain and turned it on and a button 'Approve with security code' appeared. It asked my iCloud security code and after it asks for 6 digit verification code that has been sent to my old phone number that I no longer have access to. After trying to find where I can change my number. I already went to settings > phone > my number and entered my current number but the phone still has sends the verification code to the old number.
I am using an iPhone 6 with iOS 8.1
Also tried to set it up on the a macbook with Yosemite but it also send the verification code to the old number.
Best Answer
On your iPhone, go to Settings → iCloud → Keychain and switch Keychain off then on again.
Tap "Approve with Security Code", tap "Forgot Code" and then tap "Reset".
Follow the instructions to reset iCloud keychain and create a new passcode.
You will then be prompted to update to your new number.