[Please Help] Dynamic Page Dropdown Filter Option GRAY!

Hello everyone,

I created a dynamic page using Wix App Collection (products).
This way anytime I update my product list, it automatically updates in my dynamic page.

In the Dynamic Page, I’ve added the dropdown filter.
I connected the drop down to the Wix App Collection.
However, many of the columns (or fields) in the collection cannot be chosen to be used as a filter parameter. Please see screenshot below.

Ribbons, Custom Text Fields cannot be chosen to use as a filter.
Is there a way to activate these fields to use for filtering?
Any help would be appreaicted. Thank you so much in advance.

image

If anyone knows about it please help.