Ordered phones online, cant create account.

Hey there, I recently ordered 3 phones online. Before the phones arrived I thought I'd create an account and get myself familiar with their app and website.

It's asking for a phone number. Just says number not found. Also anyone else have any experience on what I do when I get the phones? It's going to have numbers ported over from att. I thought it was weird it didn't ask me for account number and transfer pin. 

Just wondering how easy or difficult it will be once phones arrive.

Thanks in advance