two-step verification

Follow these steps

1. Sign in to appleid.apple.com.
2. In the Sign-In and Security section, click Account Security.
3. Click Turn Off two-step verification. Click again to confirm.
4. Create new security questions and verify your date of birth.

You'll get an email confirming that two-step verification for your Apple ID is off.

Beware though, that 2 factor authentication cannot be turned off if you turned it on longer than 14 days ago. Above instructions are for two step authentication which is different from two factor authentication