This morning I was running late and missed my flight (was at the gate 12 minutes prior, but doors were closed). My mistake clearly. The gate agent then said "we were going to call you, but you don't have a phone number listed." She then showed me the screen and indeed, I had no contact information. This could have saved me because I was waiting for screening at TSA for an extra minute or two.

Does anyone know what populates this information for the gate agent? When I call into the Diamond line, it recognizes my number and links up to my account, but this must be something else.

Thanks!