get value and set in another fied in portals

Hello everyone my name is Taniguchi and im trying to get a value from a field  and set in another field from the same entity. but its not working, can anyone help me?

code that isant working

var entityName= $("#cr14d_contato_entityname").val();
var lookupGUID = $("#cr14d_contato").val();
var lookupValue = $("#cr14d_contato_name").val();
$("#cr14d_contato").change(function(){
$("#msdyn_bookableresource_entityname").val(entityName);
$("#msdyn_bookableresource").val(lookupGUID );
$("#msdyn_bookableresource_name").val(lookupValue );
})