The wireless account owner, or a Retail Authorized User can manage the account at an AT&T store.
About account access in an AT&T store
In an AT&T store, either the wireless account owner or a Retail Authorized User can manage the account. The account owner decides if they want to add Retail Authorized users.
The account owner is the person who identifies themself as financially responsible for the wireless account. This person’s name is on the bill. They can manage all parts of the account.
A Retail Authorized user is someone at least 18 years old. They can make certain account changes that the wireless account owner can also complete at an AT&T store. A wireless account can have up to 10 Retail Authorized users.
The account owner or Retail Authorized User must do these two things to manage a wireless account in a store:
Show a valid government-issued photo ID. This includes a driver's license, passport, or alien Registration Receipt Card with photo.
Provide the wireless security passcode, or other info.