Trouble activating service after activating new sim card

I already had an att phone but didn't have an active sim so I bought a new sim put it in phone and activated it online as it showed activation complete and showed the new phone number the phone died so I didn't get the number.  I tried to purchase a service plan and can't bc I don't have the phone number or account number I have been calling all day and I'm transfered from person to person that can't help me bc I can't verify the account without the phn number.   I tried  adding a phone plan by calling 611 from the device but it  keeps  transferring me to a person to complete the autodraft feature what can I do...