How can I get the access of a const inside my function?

How can I grant access to my const to be used inside a function? In this case I want to access my const catName inside my function fetchListings. I’m getting this error:

Question Updated:

ReferenceError: catName is not defined


<script context="module">

const fetchListings = async () => {

        try {
            // get reference to listings collection
            const listingsRef = collection(db, 'listings');
            // create a query to get all listings
            const q = query(
                listingsRef,
                where('type', '==', catName),
                orderBy(timestamp, 'desc'),
                limit(10)
            );
            // execute query
            const querySnap = await getDocs(q);

            let lists = [];

            querySnap.forEach((doc) => {
                console.log(doc);
            });

        } catch (error) {
            console.log(error);
        }
    };
    fetchListings();
</script>

<script>
    import { page } from '$app/stores';
    // export the const catName to the function above
    export const catName = $page.params.catName;
</script>

Hi {catName}!