Primefaces : Keep the p:dialog if empty, show the messages required and show errors messages

Question

here is my problem, I have tried different ways of doing what I want but I can't do it.

I would like my p: dialog to remain on the page as long as there are errors in the forms (errors specified in the bean and if ever the fields are empty) unfortunately I cannot display my error messages in this p: dialog, yet i tried h: messages, p: messages and updates in the button as well.

Can you direct me a little?

Thank you all

<p:dialog header="Formulaire de modification de mot de passe" widgetVar="dlg1" minHeight="40" >
            <p:ajax event="close" update="formModifMdp" resetValues="true" />
            <h:form id="formModifMdp" prependId = "false">
                <p:panelGrid id="pannel" columns="2" StyleClass="formConfig">
                    <h:outputText value="#{I18N['tooltip.utilisateur.changemdp']}" />
                    <p:password id="mdp" value="#{utilisateursBean.mdpNouveau}" update="msg"
                        validatorMessage="La valeur doit être comprise entre 8 et 40 caracteres"
                        requiredMessage="#{I18N['formulaire.message.required.mdp']}"
                        required="true"
                        toggleMask="true"
                        redisplay="true"
                        maxlength="40">
                        <f:validateLength minimum="8" maximum="40"/>
                    </p:password>
                    <h:outputText value="#{I18N['confirm.label.mdp']}" />
                    <p:password id="confmdp" value="#{utilisateursBean.mdpNouveau2}" update="msg"
                                validator="checkMdpValidator"
                        validatorMessage="La valeur doit être comprise entre 8 et 40 caracteres"
                        requiredMessage="#{I18N['formulaire.message.required.mdp']}"
                        required="true"
                        toggleMask="true"
                        redisplay="true"
                        maxlength="40">
                        <f:validateLength minimum="8" maximum="40"/>
                    </p:password>
                    <p:commandButton icon="fa fa-fw fa-check" style="float: right" value="#{I18N['application.button.modifier']}" action="#{utilisateursBean.modifMdp}"
                                     onclick="PF('popup').hide(); ">
                        <!--oncomplete="if (!args.validationFailed) PF('#cmpRegDialog').hide();"-->
                        <p:resetInput target="formModifMdp" />
                    </p:commandButton>
                </p:panelGrid>
            </h:form>
        </p:dialog>