Customer not showing under Roles Dropdown field

Hi there, I can’t seem to make the role ‘Customer’ show up as a dropdown choice for the Roles (Dropdown) field in my UM Registration form.

I’ve tested it out with other default WordPress roles (Subscriber, Editor, etc.) and they work fine. Somehow only Customer will not show up on the dropdown choices.

I thought it might be because I set the default customer type to Customer. But even after changing the default sign up user role of WordPress to something else, it still won’t show up under the dropdown.