I'm having some issue while converting String object to JAXBElement string object where I need to set this one

This is the target method where I need to set the value

public void setData(JAXBElement value) {
    this.data = ((JAXBElement ) value);
}

For this one, I have written code something like this

 ObjectFactory factory = new ObjectFactory();
    JAXBElement jaxbElement =  new JAXBElement(
            new  QName(ApplicationIngestionRequest.class.getSimpleName()), ApplicationIngestionRequest.class, request);

    StringWriter writer = new StringWriter();
    JAXBContext context =  JAXBContext.newInstance(ApplicationIngestionRequest.class);
    context.createMarshaller().marshal(jaxbElement, writer);
    LOG.info("JAXBElement object :\n"+ writer.toString());
    Unmarshaller u = context.createUnmarshaller();
    JAXBElement o = (JAXBElement) u.unmarshal(new StringReader(writer));

Log gives me following output

0000005511

Now when I try to set into the method as

losRequest.setData(o.toString());

It doesn't allow me to set as its expecting as JAXBElement format. Any ideas would be greatly appreciated.