https://youtu.be/bTx08ox0zA8

In video, input item “to Do” again at 3:54, the old “to Do” disappears. But it'not disappeared in my project

so I looked carefully my code…

const toDoForm = document.querySelector("#todo-form");
const toDoInput = document.querySelector("#todo-form input");
const toDoList = document.querySelector("#todo-list");
const TODOS_KEY = "todos";
const toDos = [];

function saveToDos(){
    localStorage.setItem(TODOS_KEY, JSON.stringify(toDos));
}

function deleteToDo(event){
    const li = event.target.parentElement;
    li.remove();
}

function paintToDo(newToDo){
    const li = document.createElement("li");
    const button = document.createElement("button");
    const span = document.createElement("span");
    span.innerText = newToDo;
    button.innerText = "✔";
    button.addEventListener("click", deleteToDo);
    li.appendChild(span);
    li.appendChild(button);
    toDoList.appendChild(li);
    toDos.push(newToDo);
    saveToDos();
}

function handleToDoSubmit(event){
    event.preventDefault();
    const newToDo = toDoInput.value;
    toDoInput.value="";
    paintToDo(newToDo);
}

toDoForm.addEventListener("submit", handleToDoSubmit);

const saveToDo = localStorage.getItem(TODOS_KEY);

if (saveToDo !== null){
    const parsedToDos = JSON.parse(saveToDo);
    parsedToDos.forEach(paintToDo);
}

then I found that

toDos.push(newToDo);
saveToDos();

they should exist in function paintToDo not a function handleToDoSubmit

In video, input new item in array on web => disappeared old item in array. When I did with my code, old item still exist in array with new item

I want understand why the error is not occurring and how the result is different between the video and my code.

Anyone can help this?