Multiple Customer numbers

I bought an Alienware last year and was given a customer number, and when i login i can view the order details for that customer number.

I just purchased another alienware, and even though i gave them my existing customer number over the phone when i ordered it, they have put it under another customer number.

How can i add the second customer number to my profile, so i can view the order. I searched on the dell/alienware website, and it only tells you how to add multiple customer numbers on the US site, however i am in the uk, and the uk site is different, so the steps on the faq don't work.