Error code 49

I saw another post asking this question but his problem was it happened every time and it was because he was encoding loco cards on hico settings. I have hico cards and and the zxp series 3 printer is set to hico settings. I am only encoding track 2 data and nothing else. 96% of the time, they encode and print just fine. 4% of the time during the encode process, it fails with error code 49. I check the card and it was successfully encoded with the correct data. What else can I do to find out why 4% of my cards are failing with this error code?