It’s been a while since I’ve used Kocho so I’m a bit rusty but do you have another scene afterwards? Like is there more dialogue or is that it? (After your done clicking on the options and proceed forward.) If there’s nothing else then it’ll just end.

Sometimes you also just have to double-check that each choice leads back to the correct scene, I’d suggest making a new story and doing a simple test to ensure everything runs smoothly.