How to identify a contact in the chat?

Good Morning,

just tried it without an app, but API/Token only. Got error complaining about missing scopes:

{"status":"error","message":"This app hasn't been granted all required scopes to make this call. Read more about required scopes here: https://developers.hubspot.com/scopes.","correlationId":".....","errors":[{"message":"All of the following scopes are required.","context":{"requiredScopes":["conversations.visitor_identification.tokens.create"]}}],"links":{"scopes":"https://developers.hubspot.com/scopes"},"category":"MISSING_SCOPES"}

linking to dead url:

Pls. advice