The values you enter in a facet’s “Value modifiers” field need to match the label of the value exactly.

For example, if you have a category called “Fall Collection”, the value entered in the “Value modifiers” field needs to be exactly that: Fall Collection, including spaces and capitalization.

If you have not modified the facet values with output hooks like facetwp_facet_display_value, the quickest way to determine the labels is to look at the facet value labels themselves: the labels beside the checkbox or radio button, or the options in the dropdown. Make sure to check if capitalization is not changed with CSS, for example with text-transform: lowercase.

See also