Write again and complain on Twitter too.
At GIG they are clueless, I tried to change a domestic leg at the Customer Service desk, for the very known Same Day Flight Change (confirmed) after I got an alert from EF ("E" bucket), but they didn't know what it was or how to do it, they even tried to charge me $200/250 for the change and I said, "no thanks". Went to the lounge, open my laptop and I was able to do it online in less than 3 minutes.