p:treeTable children root nodes duplicated after update - jsf

Question

I'm getting a weird behavior when I try to update a h:panelGroup with a p:treeTable from a p:tree ajax event.
I have a p:tree element updating a form based on ui:include fragments. On the first load, everything works fine, but, when I select a tree, the ajax event is fired, the p:treeTable is updated but the nodes are duplicated.
My tree is this, the select listener event (onNodeSelect) builds a p:treeNode variable, and update a flag to show the p:treeTable page:
<p:tree value="#{mbArquitectura.raiz}" style="border: none;"
dynamic="true"
selectionMode="single"
cache="false"
selection="#{mbArquitectura.selectedNode}"
var="node"
id="tree">
<p:ajax onstart="muestraLoader(); cleanPriceTreeTable();"
oncomplete="ocultaLoader(); removeDuplicatedIds();"
event="select"
listener="#{mbArquitectura.onNodeSelect}"
global="true"
update=":frmPromocion :frmPromocion:ttPrecio :panelDialogos" />
<p:ajax onstart="muestraLoader();" oncomplete="ocultaLoader();"
event="expand"
listener="#{mbArquitectura.nodeExpand}"
global="true"
update=":frmPromocion :frmPromocion:ttPrecio :panelDialogos" />
<p:ajax onstart="muestraLoader();" oncomplete="ocultaLoader();"
event="collapse"
listener="#{mbArquitectura.nodeCollapse}"
global="true"
update=":frmPromocion :frmPromocion:ttPrecio :panelDialogos" />
<p:treeNode id="treeNode">
<b>
<h:outputText value="#{node}" id="lblNode" style="color: #{node.label}" />
</b>
</p:treeNode>
</p:tree>
My updated form (:frmPromocion) is this:
<ui:define name="content" id="content">
<h:form id="frmPromocion" style="font-size: x-small">
<h:panelGroup rendered="#{mbArquitectura.agregarPromocion}">
<ui:include src="/pages/ArqSeven/ArqPromocion.xhtml" />
</h:panelGroup>
<h:panelGroup rendered="#{mbArquitectura.precio}">
<ui:include src="/pages/ArqSeven/ArqPrecio.xhtml" />
</h:panelGroup>
</h:form>
Inside the file ArqPecio.xhtml, there is the following dataTable:
<p:treeTable id="ttPrecio"
liveResize="true"
value="${mbArquitectura.raizPrecio}"
var="item"
style="width: 1200px;"
styleClass="grid-content">
<p:ajax event="expand" listener="#{mbArquitectura.priceExpand}" update=":frmPromocion:ttPrecio" />
<p:ajax event="collapse" listener="#{mbArquitectura.priceCollapse}" update=":frmPromocion:ttPrecio" />
<p:ajax event="select" listener="#{mbArquitectura.priceSelect}" update=":frmPromocion:ttPrecio" />
<p:ajax event="unselect" listener="#{mbArquitectura.priceUnselect}" update=":frmPromocion:ttPrecio" />
</p:treetable>
As I said, the inicial load works fine:
But, when I select a node from the tree, the p:treeTable nodes are duplicated, like this:
How can I fix this behaviour?