Can Connect to Resolver via Sandbox, but Not via useQuery? [solved]

I’m upgrading to ApolloServer v4. I have a resolver called messageFolders. I can connect to it successfully via Sandbox, but so far if I try via useQuery:

    const {data, error, loading, refetch} = useQuery(MESSAGEFOLDERS_QUERY, {
        variables: {"localUserId": Meteor.userId() ? Meteor.userId() : ""},
        fetchPolicy: 'cache-and-network',
        onCompleted: data => {
    }, [ Meteor.userId()]);

…I get the error:

TypeError: Cannot read properties of undefined (reading ‘watchQuery’)

Any thoughts on what this might mean?

Solved. I just wasn’t importing my new ApolloClient correctly in my React Router instance.