can't verify email address when creating AppleID

I'm trying to create an AppleID for my son, and when I try, I get all the way to the step of verifying the email address, and after retrieving the verification code from the associated email, I type it into the verification code screen and it does not go on to the next step. I know the code I type in is correct, because if I purposely mistype it, it gives me a "incorrect verificiation code" error (see screenshot). But when I type in the correct code, the little arrow spins after clicking "Verify" and then nothing happens. Does not matter whether I use Safari, Firefox or Chrome. Also have just created AppleIDs for my wife and other son (trying to set up Family Sharing), half hour earlier, on same machine, same browser, same syntax for AppleID, password, etc, etc.

What gives???? Can you help?