graphql query ".watch().valueChanges.pipe" not posting

[xbandx68]

I use graphql-code-generator to generate the services
All works fine with Mutation, but when I try to use for Query, in the chrome console nothing happen, seems that the Angular Apollo Client never Post Query and the Nodejs Apollo server never receive nothing, but only with Query call.

this are the call in the component:

getHello() {
        console.log('getHello');
        this.helloGQL.watch()
        .valueChanges
        .pipe(
          map(result => {
            console.log('got result', result);  
            //result.data.posts
        })
        );
    } 

this are the service generated by the plugin:

export const HelloDocument = gql`
    query Hello {
  hello
}
    `;

  @Injectable({
    providedIn: 'root'
  })
  export class HelloGQL extends Apollo.Query<HelloQuery, HelloQueryVariables> {
    document = HelloDocument;
    
    constructor(apollo: Apollo.Apollo) {
      super(apollo);
    }
  }

I don't know how to solve it....