Hi,
Try clicking the next button on your keyboard, also make sure you phone language is set to English, it could be playing with the date of birth .
Also if you are using a Tablet , try using a phone just for the sign-up.
Hey 
Sorry to hear you’re having trouble getting signed up for an account - if you can’t get past this screen then please give us a call on 0800 802 1281 and we’ll be happy to help!
It looks like next is greyed out
Maybe preferred name can only be one word
Did you solve this in the end