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Once you have found it, click the button "Actions" to see the details (i.e. user status):
Clicking on "Edit" leads you to a page when you can update every user data available:
The tab "Recipient fields" contains all the user's personal data:
The tab "Set recipient status" allow to change user status using the dropdown menu and then clicking on "Save" (e.g. from subscribed to unsubscribed):
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