By using opt-ins, fans can consent to subscribing to a newsletter, storing their data, or receiving information that you, as an organization, want to share with them. You can define and customize the content of the opt-in itself. If fans agree to the opt-in, they give their approval to be included in promotional communications directed at them. You can set the opt-in for all events within the account or create a separate opt-in for each event.
Note! You need to create the opt-in at Merchant level, how to do that you will read below