'Uh oh something went wrong'

This is a customer populated forum. I have no idea why you're having a problem upgrading online. I have no idea if calling would make any difference.  

I always recommend doing transactions in person.

If your intention is to upgrade with ATT next, that allows you to upgrade early turning in your existing phone and purchasing a new phone with installments, I always recommend doing transactions in person in an AT&T store and getting proof of the transaction at the time. Every effort should be made to avoid mailing a phone.

   When doing an early upgrade, and turning in your previous phone, it is required that you turn it over immediately in the store, there's no option to bring it back later.   This means you have to do a good backup of the phone you were turning in so that it can be factory reset and hand it over to AT&T at the time you acquire your new phone.   

Hey there @Thebigolduse,

Thank you for reaching out to us. We are here to help you in any way possible. There are a few ways around that error message that you're getting.

Allow us to assist. To complete your upgrade:
-Contact the number presented in the message if you haven't already.
-Clear your browser's cache and history and try again to complete the order, or use another browser like Mozilla Firefox.
-Wait 1-2 days and try again. It's possible the website is undergoing scheduled maintenance.

Let us know how this worked for you.

Thank you for visiting the AT&T Community Forums.

David, Community Forums Specialist.

Their is no number provided in the message 

Hi @Thebigolduse, after reviewing your concern and trying to resolve through the Community Forums, it looks like you may need more account specific support.  To assist you best, we encourage you to review our Contact Us page (https://www.att.com/support/contact-us/) to identify what method you’d prefer to reach out for this account level help.  You can call, chat, or reach out via social media and we can review your specific issue and provide you support.  We’re sorry we weren’t able to resolve your concern directly in the forums, but let us know if we can assist with anything else.

Please reach out to us if you require further help. 

Thank you for contacting AT&T Community Forums.

Andrew, AT&T Community Specialist.