Good grief. Bring it back to dealer. This is unusual.
As to you other question, don't rely on your GOM, guess o meter. Do the calculus in your head. You know the capacity, around 27KwH, you know how much you used, i.e. the new percentage, you can see the MperKwH on the screen. This is your true estimated range, not the GOM which does a calculation but no one knows the formula.
For urban stop and go, you should be getting 2.5 to 3 MperKwH unless you hot foot it at starts. For highway, you should be betting 3.5 to 4 MperKwH unless you are darting in and out of traffic. Since you are at 89%, it informs you are using the accelerator more than you need to for best mileage. Try to stay off the brake as well is another tip.
Jeff in NYC
MB '17 B250e; MB '06 E500W; MB '81 380SL