I've been unable to get Delta to credit a BOS-GRU leg of a BOS-GRU-VIX round trip flight that I took in September. It was booked through LATAM. I've submitted the form to request missing miles twice. The ticket number, which I assume is the "order number", on a LATAM reservation, does not fit the format of what is expected on the mileage credit request, so I had to fudge some extra numbers in it and explain in the comments. What's the best way to proceed?