Problems using SelectOneMenu primefaces

I have a problem updating the data of a SelectOneMenu in primefaces, as the code below suggests, I have a button that when clicked, brings data from a WebService and stores it in a Devices variable on the back end and shortly after , it only throws its names to the deviceNames list, this happens because the Size of the list with the names and OK, nothing happens in my SelectOneMenu. I have already made many changes but so far nothing. It seems to be pretty silly but I can not seem to find the problem.

XHTML Page

<h:body>
    <p:messages autoUpdate="true"/>
    <h:form id="mainform">
        <p:commandButton id="button1" 
                         value="Configuração">
            <p:ajax listener="#{config.carregaSbcDevices}" update="panelAU"/>
        </p:commandButton>
        <p:outputPanel autoUpdate="true" id="panelAU">
            <p:selectOneMenu value="#{config.configSCBEsc}">
                <f:selectItem itemLabel="Selecione..." itemValue="" />
                <f:selectItems value="#{config.devicesName}" />
            </p:selectOneMenu>
        </p:outputPanel>
    </h:form>
</h:body>

Bean config

public void carregaSbcDevices() {
    if(this.devices == null) this.devices = new ArrayList<>();
    this.devices.clear();

    if(this.devicesName == null) this.devicesName = new ArrayList<>();
    this.devicesName.clear();

    session.getDevices(this.devices);
    for(SBCDevices device : this.devices) {
        this.devicesName.add(device.getTargetName());
    }

    System.out.println("Numero: " + this.devicesName.size());
}