The filterCheckBox function isn't working for me

const form = document.getElementById('registrar');
const input = form.querySelector('input');

const mainDiv = document.querySelector('.main')
const ul = document.getElementById('invitedList'); //global constants 

const div = document.createElement('div');
const filterLabel = document.createElement('label');
const filterCheckBox = document.createElement('input');

filterLabel.textContent = "Hide those who haven't responded";
filterCheckBox.type = 'checkbox';
div.appendChild(filterLabel);
div.appendChild(filterCheckBox);
mainDiv.insertBefore(div, ul);

filterCheckBox.addEventListener('change', (e) => {
  const isChecked = e.target.checked;
  const lis = ul.children;
  if(isChecked) {
    for (let i = 0, i < lis.length, i += 1) {
      let li = lis[i];
      if (li.className === 'responded') {
        li.style.display = '';
      } else {
        li.style.display = 'none';
      }
    }
  } else {
    for (let i = 0, i < lis.length, i += 1) {
      let li = lis[i];
      li.style.display = '';
    }
  }
});

function createLI(text) { // createLI function is called when you hit the submit button -- line 26
  const li = document.createElement('li');
  const span = document.createElement('span');
  span.textContent = text;
  li.appendChild(span);
  const label = document.createElement('label');
  label.textContent = 'Confirmed';
  const checkbox = document.createElement('input');
  checkbox.type = 'checkbox';
  label.appendChild(checkbox);
  li.appendChild(label);
  //edit button
  const editButton = document.createElement('button');
  editButton.textContent = 'edit';
  li.appendChild(editButton);
  //remove button
  const removeButton = document.createElement('button');
  removeButton.textContent = 'remove';
  li.appendChild(removeButton);
  ul.appendChild(li)
}

form.addEventListener('submit', (e) => { // when submitting this form, the inputted text is used to populate the createLI function
  e.preventDefault();
  const text = input.value;
  input.value = '';
  const li = createLI(text);
  ul.appendChild(li);

});

ul.addEventListener('change', (e) => { // handles the checkbox in the list item
  const checkbox = event.target;
  const checked = checkbox.checked;
  const listItem = checkbox.parentNode.parentNode;

  if (checked) {
    listItem.className = 'responded';
  } else {
    listItem.className = '';
  }
});

ul.addEventListener('click', (e)=>{ // remove and edit button handler
  if (e.target.tagName==='BUTTON' ){
    const button = e.target;
    const li = e.target.parentNode;
    const ul = li.parentNode;
    if (e.target.textContent === 'remove'){
      ul.removeChild(li);
    } else if(e.target.textContent === 'edit'){
      const span = li.firstElementChild;
      const input = document.createElement('input');
      input.type = 'text';
      input.value = span.textContent;
      li.insertBefore(input, span);
      li.removeChild(span);
      button.textContent = 'save';
    } else if(e.target.textContent === 'save'){
      const input = li.firstElementChild;
      const span = document.createElement('span');
      input.type = 'text';
      span.textContent = input.value;
      li.insertBefore(span, input);
      li.removeChild(input);
      button.textContent = 'edit';
    }
}                   
});