Cant activate keychain cause the phone number on my iCloud changed! Tips?

Go do a different iOS device or Mac that has iCloud keychain enabled and change the number as follows:

• Devices using iOS 7.0.3 or later: Tap Settings > iCloud > Account, then tap Keychain. Check that the phone number listed under Verification Number is correct. If not, enter another phone number.
• Macs using OS X Mavericks v10.9 or later: Choose Apple () menu > System Preferences. Click iCloud, then click Account Details. Check that the phone number listed under Verification number is correct. If not, enter another phone number.

This does not work.

- When using the iOS way the screen Settings > iCloud > Account > Keychain shows "approve with security code" grayed out. No telephone number anywhere.

- When using Apple () menu > System Preferences > iCloud > Account Details, there is no option to change anything at all. You can, however, go to "Manage Apple ID" and change your phone number. Even so, the SMS code is still being sent to the wrong number.

You have to perform the steps above on a different device or Mac that already has iCloud Keychain set up on it.

Already did that and still does not work. But I have found a solution:

On the iOS, when typing the iCloud passcode (4 digit), go to the "I forgot my password" option. You will be asked to repair the keychain saved configurations, choose yes. Then, type a new iCloud passcode (or the same as the previous one) and, finally, your phone number. Your mac should be able to see your iphone now to finish the keychain activation.

Sometimes Apple support is more a hindrance than a help!

Geez, man. I've been fighting with this for months now. Even Apple support couldn't help me.

Thank you very, very much!

Nobody in the apple could figure this one out for me in the apple store in Perth Aus.

Good work, Tech heads take note !!

You rock! This was simple. Every other option included having to talk to Apple. Thanks!