You have to to explicitly specify that a conversation shouldn't be propagated for a particular request. Add nocid=true
as a parameter at the end of your index.xhtml.
<error-page>
<exception-type>org.jboss.weld.context.NonexistentConversationException</exception-type>
<location>/faces/index.xhtml?nocid=true</location>
</error-page>
Refer to the following link expired conversations involving CDI and JSF