Today's customers ask ytkah wordpress website has been really stubborn / category in the classification url / he says she has set up a method before ytkah still does not work, back into the site found that their site has installed yoast, then you probably know where is the problem, click on yoast seo in the Search Appearance - Taxonomies - Category URLs - Remove the categories prefix is set to Remove, as shown below
Refresh the cache, and then open the category pages, url of the category has been eliminated. Encounter the same problems friends can try
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