1. Log in to your Substack account and head to your publication's Settings page. Click on Community in the left navigation bar.
2. Click on "Manage bans" next to "Manage user bans".
On this page, you can either:
- Enter a list of emails in the dialog box to ban, separated by commas.
- Upload a .csv file listing each email in a separate line, without commas.
After entering an email address, you can select which kind of ban you want to apply (commenting, subscribing, or both) and how long you want the bans to last (1 day, 30 days, 90 days, 1 year, or forever).