Description: The value for the language attribute is not set to a valid language code. Valid language codes must be used to programmatically determine the human language of pages and parts of content.
Context: The language attribute has a strict set of valid values that it allows, any invalid values are ignored. Verify if these tags are necessary for your content as well.
<span lang="ES-TRAD">
<span class="il" style="transition: none 0s ease 0s;">Nathalie</span>
<span class="il" style="transition: none 0s ease 0s;">Ginapp</span>
</span>
How to fix it: Make sure you are using a valid BCP 47 language code for the language attribute.
<span lang="es">
<span class="il" style="transition: none 0s ease 0s;">Nathalie</span>
<span class="il" style="transition: none 0s ease 0s;">Ginapp</span>
</span>Techniques: H58