Selling on Amazon: Your listing is under review

Received the following email today requesting an invoice for one of my items. I have an invoice, but when I responded to the email (as requested), I got a response that messages sent to that address are not read (obviously as it came from donotreply type of email)
So how do I submit the invoice? I have no cases or warnings on my account that I need to appeal to:

Hello,

Why did I receive this message?
In order to ensure the authenticity of items for sale on Amazon, we are reviewing your inventory for the ASIN listed at the bottom of this email. Your listings are still active, but we would like to work with you to complete our review. When you reply to this email, do not delete this code: {amazon.pqref.36bdff61c45f292cdf9c2aa86c821d57}

What happens now?
Within 7 days, please reply to this email with the following:

• Copies of invoices or receipts from your supplier issued in the last 365 days. These should reflect your sales volume during that time.
• Contact information for your supplier, including name, phone number, address, and website.

You can send .pdf, .jpg, .png, or .gif files. These documents must be authentic and unaltered. We may call your supplier to verify the documents. You may remove pricing information, but the rest of the document must be visible. We will maintain the confidentiality of your supplier contact information.

How do I send the required information?
Please submit this information by replying to this email. When you reply to this email, do not delete this code: {amazon.pqref.36bdff61c45f292cdf9c2aa86c821d57}

What happens if I do not send the requested information?
If we do not hear from you within 7 days, or we are unable to confirm the information you provide, we may remove your listings.