Reset visitor ID in matomo flutter SDK

We’re currently implementing your SDK for flutter apps in our app, and we cannot find out how to unset the currently used visitor ID. The scenario is simply:

  • Mobile App User inkognito opens app > MatomoTracker.instance.initialize() auto-generates visitor ID

  • Mobile App User A logs in on a device > MatomoTracker.instance.setVisitorUserId(obtainedUserIDFromBackend)

  • Mobile App User A logs out of device > MatomoTracker.instance.setVisitorUserId(null)

but how can we unset the visitor ID back to a newly, randomly generates visitor ID? Otherwise, if after the above:

  • Mobile App User B logs in to the same device > MatomoTracker.instance.setVisitorUserId(obtainedDifferentUserIDFromBackend), which will lead to which consequence, as the visitor ID is still the same?