Upscribe saves your signups immediately after they submit your form. Mailchimp, on the other hand, does not add your subscriber until they have responded to the Mailchimp double opt-in process. To learn how to skip this process please see the “How do I skip Mailchimps double opt-in process?” FAQ item on this page.
Kindly navigate to your account page and select the checkbox beside “Skip double opt-in process (Mailchimp)” and then press Save Changes.
You can easily embed your signup form on Medium by doing the following:
Click here to learn how to turn that off.