Does it still go the same distance before the system shuts down?
If so, the new display is simply programmed wrong for your battery pack voltage, and you'd have to change those settings per the display manual if it has such a setting (or live with it if it doesn't, or change to a display that does have this ability, etc).
If it now has less range than before, the new display has changed the current limit on your controller so it's using more power per distance, so there is less available distance.
If there was a change in performance where the system feels like it works bet ter or accelerates harder or goes faster, then the latter is probably the case.
If that's true, then to get the same range you'd either have to turn down the current limit back to the previous one so it will perform like it used to, or you'd have to change your battery to one capable of supplying both the higher current (A) to maintain performance, *and* higher capacity (Ah) to increase the range.
If you're really not sure, then to find out all of what's really happening with the system, you could install a wattmeter like this (or many others)
https://www.amazon.com/gp/product/B013PKYILS/
between the battery and controller, then test with your old display, then with your new one, and find out how much current is being used either way, and how many Ah (or Wh) your battery provides from full to empty.