XML File

Sorry changed the name so now it is:
https://verasartsanddice.com/wp-content/uploads/wppfm-feeds/Dice—Polyset.xml

Hello @verasartsanddice

You will get this error on the client-side when the client (the web browser) for some reason interprets the HTTP response content as text/XML instead of text/HTML and the parsed XML tree doesn’t have any XML-stylesheet. In other words, the web browser incorrectly parsed the retrieved HTTP response content as XML instead of as HTML due to the wrong or missing HTTP response content type.

It is not a problem

But it does not display it the right way, or am I wrong?

No, it is perfeclty fine.
Enter the url in your Google Merchant center and you will see.