setValue from a ComboBox didnt work with a FreeformQuery

I have a table and a comboBox populate by a FreeformQuery:

FreeformQuery free = new FreeformQuery(“select * from table”,getConnectionPool);
container = new SQLContainer(free);
combo.setContainerDataSource(container);

It adds correctly the value to the comboBox. I tried to do something like the below code when a user clicks on a row:

combo.setValue( table.getContainerProperty(tabla_m.getValue(), "columnName").getValue().toString()) 

BUT it didnt set the value of the combo, I tried a literal value>

combo.setValue("valid value") but it didnt work.

BTW, is not the ot the listener, because it setValue of other textfields. The problem is in the setValue when a container is used i suppose