Cannot Log-in to iCloud, no place to enter verification code

Dear Forum,

There is a glitch in the iCloud log-in process on my MacBook Pro: I launch the iCloud application and enter the password and I get a six-digit verification code on my iPhone. But, there is no field to enter the verification code.

How do I resolve this?

Details:

OS 10.9.5

MacBook Pro, Retina Mid 2012

Thanks,

Steve