This XML file does not appear to have any style information associated with it.

I have a contact form posting data to a third party crm. After submit I redirect to a thank you page which is working. But I’m getting the third party crm response in other window at client side with an error “This XML file does not appear to have any style information associated with it. The document tree is shown below.”
youareapproved.com
How can I solve this?