The DLZ changes depending on aspect and speed, selected radar range, etc. The DLZ has a rectangle for the RTR (range turn and run) which is in essence a no-escape-zone where your missile is very likely to hit unless duped by flares. Above the closed rectangle is an open shall we say "three-sided-rectangle" missing its right vertical line. It reminds me of a squarish pirate's hook. That depicts the RPI (range probable intercept) zone, where you missile has a chance to hit but it depends on how the target reacts and how capable they are of maneuver.
So in your screenshot, I only see the RTR zone, a fully closed rectangle. That is your DLZ, it just isn't showing the RPI zone because for your selected radar range (5 nautical miles), that entire range is RTR, likely because your target is flying towards you. If your target was flying away from you with max afterburner going 600 knots, then you'd see your RTR zone shrink and you'd see that pirates hook of the RPI range grow.
