it seems that the social share link in spanish is creating a bad attribute that renders the AMP page invalid.
<amp-social-share type="whatsapp" data-share-endpoint="whatsapp://send" data-param-text=""Vea este artículo: TITLE -$ s" width="45" height="33"></amp-social-share>
it seems that the double quotes closes before the text "Vea este articulo: ... "