AWR2243: post processing

Tool/software:

Hi 

I'm using the AWR2243Boost +DCA 1000 for indoor data collection. I couldn't see any target response on the heat map, expect the 2D FFT heatmap shows a strong point near 0 range and 0 velocity. The chirp slope is ~35 MHz/µs and start frequency is 77 GHz. Could anyone tell me what am I missing here?

Thanks.