ValueChangeListener is not changing values in input text field and in dropdown - jsf-1.2

Question

In my application, I call the value change listener on change of values in a listbox.
The value change listener should update the values of four fields - 2 input text fields and 2 combo boxes ( dropdown boxes). The bean scope is request. I am using JSF 1.2 version.
the jsp file:
<h:selectManyListbox id="FSIBUCKET" required="true"
rendered="#{mangAreaSignOff.renderSelectedFSIBUCKET}"
valueChangeListener="#{mangAreaSignOff.handleFSIBucketValueChange}"
onchange="submit(); javascript:waiton();" style="width:230px"value="#{mangAreaSignOff.selectedFsiBucket}" >
<f:selectItems value="#{mangAreaSignOff.fsiBucketList}" />
</h:selectManyListbox>
the java code:
public void handleFSIBucketValueChange(ValueChangeEvent vce)
{
Object[] selectedFSIBucket = (Object[]) vce.getNewValue();
setSelectedFsiBucket(selectedFSIBucket);
getFSIBucketValueChangeResults();
}
public void getFSIBucketValueChangeResults()
{
Object [] tempFSIBucket = getSelectedFsiBucket() ;
String FSIBucket = getArrayToString(tempFSIBucket, ";");
List<String> result = mangAreaAPI.getFSIBucketValueChanges(FSIBucket);
mangAreaVO.setSelectedThresholdcategory(result.get(0));
mangAreaVO.setSelectedThresholdAmount(result.get(1));
mangAreaVO.setSelectedThresholdType(result.get(2));
mangAreaVO.setSelectedThresholdPercent(result.get(3));
}
I need help to identify where the flow goes wrong.
On change of the listbox value, the 4 fields are not updated. In java class I am able to see the updated values. but in screen it is not updated. Please let me know if any more explanation is needed in my question.
<h:panelGrid columns="10">
.
some other fields
.
.
<!-- Threshold Category -->
<h:panelGroup styleClass="text2"
rendered="#{mangAreaSignOff.renderInputThresholdCategory}">
<h:outputText value="MGT_LABEL_THRESHOLDCATEGORY" escape="false"
converter="com.db.smis.planus.TermConverter" styleClass="text2" />
<f:verbatim>:</f:verbatim>
</h:panelGroup>
<h:panelGroup
rendered="#{!mangAreaSignOff.renderInputThresholdCategory}">
<h:outputText value=" " escape="false" />
</h:panelGroup>
<!-- Threshold Amount -->
<h:panelGroup styleClass="text2"
rendered="#{mangAreaSignOff.renderInputAmount}">
<h:outputText value="MGT_LABEL_THRESHOLD" escape="false"
converter="com.db.smis.planus.TermConverter" styleClass="text2" />
<f:verbatim>:</f:verbatim>
</h:panelGroup>
<h:panelGroup rendered="#{!mangAreaSignOff.renderInputAmount}">
<h:outputText value=" " escape="false" />
</h:panelGroup>
<!-- Threshold Type -->
<h:panelGroup styleClass="text2"
rendered="#{mangAreaSignOff.renderThresholdType}">
<h:outputText value="MGT_LABEL_THRESHOLDTYPE" escape="false"
converter="com.db.smis.planus.TermConverter" styleClass="text2" />
<f:verbatim>:</f:verbatim>
</h:panelGroup>
<h:panelGroup rendered="#{!mangAreaSignOff.renderThresholdType}">
<h:outputText value=" " escape="false" />
</h:panelGroup>
<!-- Threshold Percentage -->
<h:panelGroup styleClass="text2"
rendered="#{mangAreaSignOff.renderThresholdPercent}">
<h:outputText value="MGT_LABEL_THRESHOLDPERCENT" escape="false"
converter="com.db.smis.planus.TermConverter" styleClass="text2" />
<f:verbatim>:</f:verbatim>
</h:panelGroup>
<h:panelGroup
rendered="#{!mangAreaSignOff.renderThresholdPercent}">
<h:outputText value=" " escape="false" />
</h:panelGroup>
.
.
.
.
</h:panelGrid>
I need to update the above 4 fields only.