TypeError: n.indexOf is not a function error for firebase/firestore v9

I am receiving a TypeError: n.indexOf is not a function error when trying to access the customers collection in my database. However, I can access the products collection fine.

This is the code I’m trying:

   const taskQuery = doc(collection(db, "customers"), where("uid", "==", user.uid))
    const loadCheckout = async (priceId) => {
        try {
            const taskDocs = await getDocs(taskQuery)

        } catch (error) {
            console.log(error.message)
        }
    }

user.uid is defined and because I can access the ‘products’ collections, the app initialisation is hooked up correctly. If I remove the ‘where(“uid”…)’ I get a ‘Missing or insufficient permissions’ error which lead me to believe there is something wrong in the rules.

Rules:

rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    match /customers/{uid} {
      allow read: if request.auth.uid == uid;

      match /checkout_sessions/{id} {
        allow read, write: if request.auth.uid == uid;
      }
      match /subscriptions/{id} {
        allow read: if request.auth.uid == uid;
      }
    match /products/{id} {
      allow read: if true;

      match /prices/{id} {
        allow read: if true;
      }

      match /tax_rates/{id} {
        allow read: if true;
      }
    }
  }
}

firestore database](https://i.stack.imgur.com/g4UcV.png)