But why did you show with only 15 minutes before the cut off? Showing up with 15 minutes before the cut off for an international flight check in when one has to check a bag is not going to turn out well as you and many other have found out.

The rules are for actually checking in with a recommendation of when to arrive at the check in. https://www.delta.com/content/www/en...uirements.html

The recommended arrival time at the airport prior to departure of international flights is 3 hours. When traveling to/from a destination outside the United States, you must be checked in at least 60 minutes before your scheduled departure time ...

As much as I hate waiting at the airport, for my last flight where I had to check a bag I showed up well over 2 hours early. I was in and out of the check in, immigration, and was at the gate all with 15 minutes of arriving at the airport. An hour before the flight immigration was backed up.

That said, I once arrived at the airport an hour before my US internal flight and could not check in at the kiosk. I tried several times before going to the desk. The GA said I missed the check in by 5 minutes. I was very confused until I realized I was looking at my inbound flight times and not my out bound which was ~50 minutes earlier. It was my mistake and I was ready to own it. Fortunately, she was able to get me on another set of flights sans any charge (as a GM). For that they got a JWD cert. And as I boarded my second flight with several other medallions who were all sitting in the back (myself included) we just laughed at each other cause we had all been put on the flight at the last minute.

For the OP. Good luck but I doubt you will get anything back. Early morning flights suck.