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You have to use 15 minutes delay between each addition because WhatsApp will ban your number if it's frequent than 15 min Aur you can use WhatsApp-web.js to add members to your group, just add a delay of 15 minutes and run the script it will do the work and if the user have added a privacy then the library will skip that member and go to the other one, ohh btw make a whole list of numbers you want to add to make things easy If you want to know more , you can ask me