GE not working although approved

Heya, for context; I’m traveling with a German passport hence it’s my only nationality, I got approved for GE at an interview in Germany 2 weeks ago. The Ticket had my KTN in it.

Yesterday I arrived at JFK T8 and entered the GE line, took a photo at the kiosk. I tried to use the GE but it failed every time. I got to the women who received my photo but said it didn’t come through, I had to go to an CPB agent who asked me all kinds of questions and also stamped my passport. I have a valid visa and GE which he could see as well, I’m just wondering why it didn’t work for me? Except the Officer being very annoyed there was not explanation.