A listing that accepts pets can show up under one pets filter on your website but not the other.
Why this happens. The two controls read two different fields from your PMS, so they can disagree. The Pets toggle in the Guests dropdown reads your listing’s pet policy, the setting that says whether the property accepts pets. The Pets allowed checkbox in the Filters panel reads your listing’s amenity list, where Pets allowed is one amenity among many.
What to check. In most PMS platforms, the pet policy and the amenity list are two separate places to edit, and setting one does not set the other. The website does not reconcile them, so however the two fields disagree in your PMS is what your guests see.