There are plenty of airports with a LH ticketing counter. I assume this is a ticket in the future? You might run into issues w/ airport desks as well since they are supposed to help primarily w/ day-of-travel disruptions. Could be a worth a try, but I wouldn't travel to the airport to do that - just stop by when coming through anyway.
The chat bot I understand, but why did the phone agents not want to help? What was their reasoning?