The blacklist is used to prevent customers from purchasing from your instance by blocking them on the Order Import API call. Blacklisted customers do not reach the gateway.
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Go to Admin and select Blacklist:
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From here you can search your blacklist as well as add to it.
Add to Blacklist:
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You can either import a file via CSV by clicking IMPORT FILE or add who you want blacklisted individually by clicking the + button.
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When the + button is selected, a dialogue box will pop up which will allow you to specify what you want blacklisted; card bin, country/state, phone number, email address, IP address, and address.:
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