Why is id_cust_fb_cust undefined?

I am playing with emberFire / Ember Data but can't find why this code will not working ??? The var id_cust_ fb_cust is always undefined ? When i look in ember inspector the query's works fine ! What am i doing wrong ???

import Ember from 'ember';
export default Ember.Controller.extend({
 actions: {
     fixit: function() {
     var teller = 11;
     var _this = this;
     var strTeller = teller.toString();
    _this.store.findRecord('address',strTeller).then(function(address){
        var id_cust_presta_addr = address.get('id_customer');
        console.log('Id Customer Presta in address is :' + id_cust_presta_addr);
        _this.store.query('customer', {
                orderBy: 'id_customer',
                equalTo: id_cust_presta_addr
            }).then(function(customer){
                var id_cust_fb_cust = customer.get('email');
                console.log('Id Customer Presta in CUSTOMER is :' + id_cust_fb_cust + 'voor : ' + id_cust_presta_addr );
            })

    });
    } //fixit
} // actions

}); // export