When performing your migration, you have to fill in your store URL address to the blank bar.
Please note, Big Cartel is a hosted shopping cart that allows merchants to change the initial domain name of your store to a unique one. However, in order to perform automated data migration, you have to use the default URL address. It has to look like www.my-store.bigcartel.com as the only required data for your Big Cartel store.
In case you have any other questions, please reach out to us via: