title: GraphQL error: Cannot query field 'mutation_name' on type 'Mutation'
body: <p>I am trying to mutate a mutation. The mutation does exist and works fine on my graphql playground. but as I implement it in my react component, I get error. Queries work fine though. By the way, I need client in my code so I definitely have to use ApolloConsumer.</p>
  
  <p>I tried using client.mutate like <a href="https://github.com/apollographql/apollo-client/issues/2762" rel="noreferrer">https://github.com/apollographql/apollo-client/issues/2762</a></p>
  
  <pre><code>export const LOGIN = gql`
    mutation LOGIN($email: String!, $password: String!) {
      login(email: $email, password: $password) {
        email
      }
    }
  `;
  class LoginComponent extends Component{
    render(){
      return(
        &lt;ApolloConsumer&gt;
          {client=&gt;{
            return(
              &lt;Button onClick={()=&gt;{
                client
                  .mutate({
                    mutation: LOGIN,
                    variables: {
                      email: "test@test.com",
                      password: "test"
                      }
                  })
                  .then(result =&gt; {
                    console.log('result', result)
                  })
                  .catch(err =&gt; {
                    console.log("err", err);
                    alert(err.toString());
                  });
              }}&gt; 
                OK
              &lt;/Button&gt;
            )
          }}
        &lt;/ApolloConsumer&gt;
      )  
    }
  }
  </code></pre>
  
  <p>I expect to get success but I get Error: GraphQL error: Cannot query field 'login' on type 'Mutation'. (line 2, column 3):
    login(email: $email, password: $password) {
    ^</p>