Approve This iPad modal window corrupted

I have restored an iPad, and the iPad is now telling me I need to 'Approve it from another device' otherwise some account services won't be available. I have signed in with my Apple ID, entered the iPads PIN code and the next screen is the Approve This iPad modal window.

However this window is not readable - it's corrupted (see below). The text is hanging off the side. Anyone know how to proceed and get this iPad approved?