There are two names associated with every Ava account, each serves a different purpose.
The display name is the name used to attribute text to the appropriate speaker in a group conversation.
The Ava name is the identifier used to connect with other users for a group conversation. It is also used at events where Ava is being offered to receive the captions for a specific room. It is displayed with the "&" in front of it.
Here's where to find your Ava name:
In the Contacts screen, it's in the blue banner at the top.
In the Profile screen, it's at the top under your display name.
Here's how to change your Ava name:
Go to the Profile screen to access the Settings menu, then scroll down and select Change Ava Name. Remove the existing Ava name and enter your new one.