Return Flux JsonObject from N1QL query output


I am trying to execute a N1QL query using the @Query annotation as below:

@Query(“SELECT META().id as __id, META().cas as __cas, user_id, firstname, lastname, city, phonenumber, email, postalcode FROM userData where user_id= $1”)
Flux <JsonObject> findByUserId(String user_id);

I want to retrieve the data into JsonObject and return this flux object back to the controller. But this always gives null. If I use a POJO class for example Flux<User> then I do get the data.

Is there something missing or is there another method to return data into JsonObject.