Agreement Number Apple Care Iphone

Hi, I am trying to register my Apple Care for my iPhone 5S but everytime I try and put in the number I get an error message underneath asking me 'Please enter a valid enrollment number'

I am clueless what to do next.. As I am 99% sure that it's the right number from the booklet inside the Apple Care Box I am typing in.

HELP!

Does it matter that I am registering a UK iPhone 5S, with a French Bought Apple Care package while living in Denmark?

Any help would be great.

Thanks in advance.