One user gives a book to another. I want to write books into a definite table 'Borrowed books'. How must I change the rules? For now I've got an exeption: W/Firestore(21240):[Firestore]: Write failed at Borrowed books/books: Status{code=PERMISSION_DENIED, description=Missing or insufficient permissions., cause=null}
CollectionReference borrowedBooksTable =
FirebaseFirestore.instance.collection('Borrowed books');
final borrowedBooksReference =
borrowedBooksTable.doc('books');
await borrowedBooksReference.set(borrowedBook.toJson());