Hi @yelenabuck, thanks for reaching out, if it’s still occurring, your question about how to remove a pop-up would be best suited for the support group at Mailchimp to review. Here at the plugin team, we focus on the engineering of the plugin between your store and Mailchimp.
They would be able to access your account and walk you through that process. You can reach out to their excellent customer service team here: https://admin.mailchimp.com/support/woo-forum. You should be able to chat with them and take things from there.
Thanks again for getting in touch, let us know if there’s anything else we can do.