Not sure if within the scope, but the model can't detect whether the text input should be separated by the period punctuation. In other words, it can't detect whether a text input actually represents two sentences.
e.g.
fastpunct.punct([
"There are three ways to slice a fish on the left on the right and on the middle after you sliced the fish you can go to the house"], correct=True)
yields
['There are three ways to slice a fish on the left, on the right, and on the middle, after you sliced the fish, you can go to the house.']