Solr 9.2.1 server SolrJ index and retrieve issues

Question

1. Env: Solr 9.2.1 docker image
2. I am using Parent POJO, Child POJO and indexing with SolrJ library
3. I am looking for SolrJ solution who could help me
4. managed-schema.xml updated with <field name="_nest_parent_" type="string" indexed="true" stored="true"/>

There are issues which i noticed

1. Parent and Child POJO name, c1 attribute indexes as multivalued, i need only single value

2. Parent id is not nesting with child

3. When i retrieve based on query , i get child null

            import java.util.List;
            import org.apache.solr.client.solrj.beans.Field;
   
        public class Top {
            @Field
            private String id;
            @Field
            private String name;
            @Field(child = true)
            private List<Child> childs;
   
            public Top() {
            }
   
            public String getId() {
                return id;
            }
   
            public void setId(String id) {
                this.id = id;
            }
   
            public String getName() {
                return name;
            }
   
            public void setName(String name) {
                this.name = name;
            }
   
            public List<Child> getChilds() {
                return childs;
            }
   
            public void setChilds(List<Child> childs) {
                this.childs = childs;
            }
        }
   
   
        import org.apache.solr.client.solrj.beans.Field;
   
        public class Child {
            @Field
            private String id;
            @Field
            private String c1;
   
            public Child() {
            }
            public String getId() {
                return id;
            }
            public void setId(String id) {
                this.id = id;
            }
            public String getC1() {
                return c1;
            }
            public void setC1(String c1) {
                this.c1 = c1;
            }
        }
   

Main

HttpSolrClient solrClient = new HttpSolrClient.Builder(solrBaseURL + "/" + core_users)
            .withConnectionTimeout(1000, TimeUnit.MILLISECONDS)
            .withSocketTimeout(2000, TimeUnit.MILLISECONDS)
            .build();
try{
                    // Index
                    Child c1 = new Child();
                    c1.setC1("C1");
                    c1.setId("P0Child0");
                    Top top = new Top();
                    top.setId("P0");
                    top.setName("P0_Name");
                    top.setChilds(Arrays.asList(c1));

                    solrClient.addBean(top);
                    solrClient.commit();
                    
                    
                    // Retrieve
                    Map<String, String> map = new HashMap<>();
                    map.put(CommonParams.Q, "id:P0");
                    SolrParams solrMap = new MapSolrParams(map);
                    QueryResponse queryResponse = solrClient.query(solrMap);
                    System.out.println(queryResponse.getResults());
              List<Top> beans = queryResponse.getBeans(Top.class);
                    System.out.println(beans.get(0).getChilds());

        } catch(Exception e) {
            e.printStackTrace();
        } 

Sample result http://localhost:8983/solr/users/select?fl=*%2C%5Bchild%5D&indent=true&q.op=OR&q=*%3A*&useParams=

    {
  "responseHeader":{
    "status":0,
    "QTime":2,
    "params":{
      "q":"*:*",
      "indent":"true",
      "fl":"*,[child]",
      "q.op":"OR",
      "useParams":"",
      "_":"1689603922013"}},
  "response":{"numFound":2,"start":0,"numFoundExact":true,"docs":[
      {
        "id":"P0Child0",
        "c1":["C1"],
        "_version_":1771697482056597504},
      {
        "id":"P0",
        "name":["P0_Name"],
        "_version_":1771697482056597504}]
  }}