PrimeFaces Ajax call only once through the application - ajax

Question

Hi i am developping a jsf spring application and i am using primefaces library
what i found is that ajax calls
<p:ajax listener="#{etatTest.onClientChange}" update="pret"/>
<p:ajax listener="#{etatTest.onEntiteChange}" update="clients"/>
<are not firing at all , i tried to debug but nothing
this is my bean
#Named
#ViewScoped
public class EtatTest implements Serializable{
#Autowired
private IEntiteManager entiteManager;
private Integer idEntite;
private List<Entites> ents;
private Entites entite;
#Autowired
private ICrmClientManager clientManager;
private Crmclients crmClient;
private List<Crmclients> crmClients;
#Autowired
private IBqPretManager bqpretManager;
private Bqpret pret;
private List<Bqpret> listPret;
#PostConstruct
public void init() {
ents =entiteManager.AllEntites("03052021105404", 1);
}
public void onEntiteChange()
{
if(entite !=null && !entite.equals(null)) {
crmClients=clientManager.getByEntite(entite);
}else {
crmClients=new ArrayList<Crmclients>();
}
}
public void onClientChange() {
if(crmClient==null && !crmClient.equals(null)) {
listPret = bqpretManager.listBqpret(null,null,null ,crmClient.getId(),null,null, null,null,null, null);
}else {
listPret=new ArrayList<Bqpret>();
}
}
//getters and setters
<h:form>
<p:growl id="msgs" showDetail="true" skipDetailIfEqualsSummary="true"/>
<p:panel header="Select a Location" style="margin-bottom:10px;">
<h:panelGrid columns="2" cellpadding="5">
<p:outputLabel for="entite" value="Entity: "/>
<p:selectOneMenu id="entite" value="#{etatTest.entite}" style="width:150px">
<p:ajax listener="#{etatTest.onEntiteChange}" update="clients"/>
<f:selectItem itemLabel="Select Entite" itemValue="" noSelectionOption="true"/>
<f:selectItems value="#{etatTest.ents}" var="p" itemLabel="#{p.libelle}" itemValue="#{p.id}"/>
</p:selectOneMenu>
<p:outputLabel for="clients" value="Client: "/>
<p:selectOneMenu id="clients" value="#{etatTest.crmClient}" style="width:150px">
<p:ajax listener="#{etatTest.onClientChange}" update="pret"/>
<f:selectItem itemLabel="Select client" itemValue="" noSelectionOption="true"/>
<f:selectItems value="#{etatTest.crmClients}" var="p" itemLabel="#{p.libelle}" itemValue="#{p.id}"/>
</p:selectOneMenu>
<p:outputLabel for="pret" value="Pret: "/>
<p:selectOneMenu id="pret" value="#{etatTest.pret}" style="width:150px">
<f:selectItem itemLabel="Select pret" itemValue="" noSelectionOption="true"/>
<f:selectItems value="#{etatTest.listPret}" var="p" itemLabel="#{p.libelle}" itemValue="#{p.id}"/>
</p:selectOneMenu>
</h:panelGrid>
</p:panel>
</h:form>