Upgrade to 2.1 multiples items in my Store

[Gaspard22]

Hello,

In a List view, i display an object containing associated data
this record is an 'Event' which has many 'Tasks' which has many 'dental_task_event'

Event
|_ Tasks
|_ dental_task_event

my problem is that now after the upgrade to 2.1 the tasks are multiplied in my store, while in 2.03 that was working well

here's my Event model

Ext.define('CWFSE.model.Event_evt', {
    extend: 'Ext.data.Model',
    requires: ['CWFSE.model.Task','CWFSE.model.DentalEvt'],
    
    config: {
        idProperty: 'EVT_ID',
       identifier: 'uuid',
        fields: [
        {name: "EVT_ID", type: "int"},
        {name: "USR_ID", type: "int"},
        {name: "CON_ID", type: "int"},
        {name: "EVT_TYPE", type: "string"},
        {name: "EVT_NAME", type: "string"},
        {name: "EVT_START", type: "string"},
        {name: "EVT_END", type: "string"},
        {name: "EVT_MSG", type: "string"},
        {name: "EVT_COLOR", type: "string"},
        {name: "EVT_STATE", type: "string"}
                 ],
         associations: [
    {type:'hasMany', model:'CWFSE.model.Task', name: 'tasks', associationKey:'tasks'},
   
    ]
    }
    
});

my tasks model

Ext.define('CWFSE.model.Task', {
    extend: 'Ext.data.Model',
    config: {
        identifier: 'uuid',
        fields: [
        {name: "ETK_ID", type: "int"},
        {name: "EVT_ID", type: "int"},
        {name: "ETK_NAME", type: "string"},
        {name: "ETK_POS", type: "string"},
        {name: "ETK_DURATION", type: "string"},
        {name: "ETK_AMOUNT", type: "string"},
        {name: "ETK_MSG", type: "string"}
                 ],
        associations: [
         {type:'hasMany', model:'CWFSE.model.DentalEvt', name: 'dental', associationKey:'dental'}
         ]
    }
});

my events are loaded by a JsonP call,

Ext.define('CWFSE.store.Event_evts', {
    extend: 'Ext.data.Store',
    requires: ['CWFSE.model.Event_evt'],
    xtype:'EventStore',
    config: {
        model: 'CWFSE.model.Event_evt',
        storeId: 'eventActe',
        autoLoad: true,
              proxy: {
            type: 'jsonp',
             url: 'http://192.168.0.34/php/erwann/events.php?id=5',
             callbackKey: 'callback',
            id : 'eventProxy',
            reader: {
                type: 'json',
               rootProperty:'events'               
            }
        }
    }


});

and my tasks are feeded with this part of code

fn: function(view, index, item, e){
                                var rec = view.getStore().getAt(index);
                                console.log(rec.get('tasks'));
                                var mysheet = new Ext.Sheet(
                                     
                            {
                                height:400,
                                layout:'vbox',
                                stretchX:true,
                                items:[
                                    {
                                        xtype:'list',
                                        layout:'fit',
                                        store :Ext.create('Ext.data.Store', {
                                                model: 'CWFSE.model.Task',// use a model
                                                data: rec.get('tasks'), // set the store data as the tasks array
                                                }),

[Gaspard22]

adding

idProperty: 'XX_ID', to my model solved this pb