Problem whith h:commandButton action

[nassij.nassij.zouhair.hotmail.com]

Hello everyone;
Here are the details of my problem:
I have userHome.persistWithAffectation an action that I invoke from a commandButton

<h:commandButton id="save"
action="#{userHome.persistWithAffectation}"
rendered="#{!userHome.managed}" image="/img/disk.gif">
</h:commandButton>

The problem is that by invoking this action - which will persist my data and then make a simple treatment he crushes the values of user sessions by the value that I have come. and  in Debug mode I realized that it does not in my method.

public String persistWithAffectation()
     {
          super.persist();
          societeUserHome.getInstance().setSociete(this.currentSociete);
          User user = this.getInstance();
          societeUserHome.getInstance().setUser(user);
          societeUserHome.persist();
          this.getInstance().getSocieteUsers().add(societeUserHome.getInstance());
          return "persisted";
     }