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2. If you have a ManyChat Free plan, you will need to contact ManyChat support via email and ask them to send you a PSID CSV file.
You need to import the resulting file into Smart Sender as described here: Importing users from other platforms before that, by connecting your Facebook page to Smart Sender as described here: Facebook connection
How to disable ManyChat from your Facebook page?
IMPORTANT! Disconnect the ManyChat application from your page only after a successful transfer of users.
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