Vivox: What causes VxAccessTokenAlreadyUsed (20120) errors?

VxAccessTokenAlreadyUsed (20120) errors occur when you try to use a VAT (Vivox Access Token) that has already been used.

Tokens are designed to be unique and used once. You must generate a new VAT when performing a VAT-required action (such as signing in, joining a channel, or performing an admin mute), and the token cannot be reused.

If a VAT is revoked through the Vivox Web API and is then used by a player, the VxAccessTokenAlreadyUsed error is returned.

If a user is disconnected, you must generate new VATs for any new operations. Even if a user is signing in again with the same username, or is joining the same channel that they were previously in, you must generate a new VAT. Do not reuse a VAT after it has been used.

Example

If you were to generate a VAT for login at 00:00:00, and then you attempt to use it at 00:00:01, the token would be valid and work. If a user got disconnected at 00:00:10 and then attempted to sign in again with the same VAT, you would receive the VxAccessTokenAlreadyUsed (20120) error.