You used a keyword in `rel` that is not recognised. If the rel attribute is absent, has no keywords, or if none of the keywords used are allowed according to the definitions in this specification, then the element does not create any links.

# How do I fix this ?

Make sure that you haven't misspelled the keyword or use a recognised keyword instead. Currently you can use the following:

* alternate
* author
* help
* icon
* license
* next
* nofollow
* noreferrer
* prefetch
* prev
* search
* stylesheet
* tag

# Resources

* [The link attribute](https://html.spec.whatwg.org/multipage/semantics.html#the-link-element)
* [W3C links](https://www.w3.org/TR/html5/links.html#linkTypes)
* [Bad value first for attribute rel on element link](http://stackoverflow.com/questions/16133223/validation-bad-value-first-for-attribute-rel-on-element-link)