@authorizenetdev I couldn't find a place to report this. The ARBCreateSubscriptionRequest API reference indicates the billTo can have a phoneNumber and faxNumber. This appears to be incorrect based on API error responses I'm receiving as well as the XSD.
https://developer.authorize.net/api/reference/index.html#recurring-billing-create-a-subscription
Hello Gregor,
I would suggest making a post to the Developer Forum. We have hundreds of developers onsite, that can help review and provide some guidance: bit.ly/2IDt7ER.
Regards,
Authorize.Net | Specialized Support