XML Formatting Error from Google Merchant

does anyone see an issue with the following ... we're stumped

http://xxxxxxxx/admin/google.merchant.c ... nments.xml = link to data feed

first product in data feed:

-<google_merchant_center_feed_attribute_assignments><assignment>
<opencart_field>Product Category</opencart_field>
<opencart_field_value>Accessories</opencart_field_value>
<google_attribute>google_product_category</google_attribute>
<google_attribute_value>Home & Garden</google_attribute_value>
</assignment>

thanks !!

also known as XML tag mismatch