This option works for custom fields and price. If you are store the information as an attribute, you need to copy it over to a custom field to use this facility.
Attribute filter workaround
The multi-range slider is not available for attribute filter right now. This is due to complications with the way woocommerce stores data for product attributes which makes it inefficient for this purpose.
Instead, what you can do is to store the specific attribute as custom fields as well on each product. Now you can use that custom field to provide a multi range slider filter (as well as sorting if you need).
Going to each product page and saving the attribute as a custom field can be time consuming. There are more efficient ways to accomplish this, covered in this doc.
Once you have the attribute saved as a custom field, you can proceed with creating a custom field filter and using the multi-range slider in that element.
Settings to create custom field range slider
The settings for Price range filter are very similar.