VANTIQ does not provide a mechanism for storing (or retrieving) contact information for the users associated with accounts
VANTIQ authentication requires the user to provide a unique account name that is validated via a unique email address. Once authenticated, the email address used for validation is irrelevant – except that it can NOT be used to validate any other account on this VANTIQ system. That email address is NOT used for authorization to VANTIQ resources.
An authenticated account is authorized to VANTIQ namespaces via invitations sent to any email address. The invitations are processed within the context of the authenticated account.
The email field you see when querying against the system.users Type is an obsolete vestige of a long-retired mechanism (the name, phone, etc. fields are also obsolete).