Importing Unsubscribed Users via CSV
Go to Voting > Scroll down to Access > Open Voters’ list block.
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Under Voters’ list, click Import list of Voters (CSV).
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Prepare a CSV file with three columns Name, Email, and with the value 1 in the third column.
CSV example:
test1@ducalis.io,Olivia Johnson,1
test2@ducalis.io,John Smith,1
Exporting Unsubscribed Users to CSV
Under Voters’ list, click Export to CSV.
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Wait for the file to be generated. Once generated, you can download the file.
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Unsubscribed users will have a non-empty value in the all_unsubscribed_at field. This field contains the date the user unsubscribed.
Importing Unsubscribed Users via API
Find the article here – Open API.