Not receiving 2 Factor verification code

I'm trying to setup my wife's new iPhone 6s - she had 2 Factor authentication turned on. The setup process is asking for a verification key and it wants to send the code to either her iPhone 6s or an SMS to her phone number. Neither of the methods is actually delivering a code.

The phone is on wifi and is has a "AT&T" showing for service.

She of course doesn't have her recovery key - but it shouldn't matter - we have two of the three things - her password and a trusted device - the problem is the code isn't coming through to the trusted device.

Thoughts?