Existing users are customers whose Engage Voice accounts were created before April 2020. This means their accounts were not originally linked to RingCentral Office, as opposed to new users whose RingCentral Office accounts are created together with their Engage Voice accounts.
To provide our customers with the best-in-class support, RingCentral will link all existing Engage Voice accounts to RingCentral Office. Your RingCentral Office account will be created automatically at no additional cost, and your main Account Contact should receive an activation email for RingCentral Office with information about how to log in. (UPDATE: This email was sent to all remaining unlinked customers in mid-December of 2020)