The TRUGLO 4x32mm Crossbow Scope comes with a great feature of having Range Finder/BCD reticle designed for crossbows. The different yardage lines (stadia lines) you see are not necessarily representing 20, 30, 40 and 50 yards respectively. In a perfect scenario, they might each represent ten yard gaps in range. Due to different crossbow performance values, speed of the bolt, weight of the bolt, broadhead, or target point, vane configurations, there are many factors influencing flight and POI (Point Of Impact) results.
Where your arrows find their zero/POI is something you will need to discover through shooting results before or beyond these theoretical 10 yard increments. It is quite possible for a sight to work at two yardages, in your case, 20 and 30 yards, and not hit the next mark, presumably 40 yards. In your case, your POI is high, which might indicate a faster speed of your bolt. This being the case, you will need to discover through actual shooting results, the distance that best coordinates with the third crosshair down, somewhere past 40 yards. This will probably also be the case with your fourth crosshair, actual shooing will determine the distance of the convergent POI result. Once these two longer POI distances are confirmed, you can then make a note for reference.