In this post, you’ll learn more about the Error cardholder_phone_number_required that is returned when working with the Stripe API
Stripe API Error
cardholder_phone_number_required
Stripe API Error Description
You must have a phone_number on file for Issuing Cardholders who will be creating EU cards. You cannot create EU cards without a phone_number on file for the cardholder. See the 3D Secure Documenation for more details.