If you've connected other 3rd party applications to Eventbrite, there's a good chance you already have the proper permissions configured in your account.
Sometimes the initial import will work, but then new events stop coming through. We will get a 403 error on our end, which means we (Fomo) are not allowed to add webhooks to your account + import data from the webhooks.
You can enable these webhook/API permissions by navigating to your Organization Permissions page within the Eventbrite admin panel, and confirm that your users have a role with Webhooks enabled. You can verify this by clicking on the Roles tab and scrolling down into the Organizations header.