The software uses a 10 point running average of the magnitude to find the 0db crossover so the crossover frequency needs to be greater than ~30Hz to be detected. You can always just look yourself where the crossover is and what the margins are. In your case the crossover is ~5HZ with huge phase and gain margins. You should be able to crank up gains considerably, which will push up the crossover frequency, and then the numbers should be displayed.
HTH