It is working as desired, i did the code with some help of course; but I just want a slight change which is that when it is displayed the sum result (either the "erro" word or the sum answer when its less than 99), it would stay there as long as i press the resetButton, which is the one that resets my counters back to 0.
And i think all is in the //Sum functionality section, because as you can see that section its looped (because it was the only way to make it work), but what i really want is what was previously described, that my result would stay there in my displays until i press my resetButton again.