Track demo produces weird values

[jazzseow]

I ran track demo with ./trackApp.out -s seqmap.txt -m det -f mot using the det.txt provided in the MOT16 data and some of the values in the output (e.g. MOT16-02) are off, like -nan values or pixel values bigger than the image size, as shown below.
216,84,-79658.6,-nan,0,-nan,1,-1,-1,-1,1

I am using dlib-19.8 with DLIB_ISO_CPP_ONLY set to ON, openCV-3.4