I'm trying to run my code for my To do list project but keep getting the error (cannot read appendChild).

let addToDoButton = document.getElementById('addToDo');
let toDoContianer = document.getElementById('toDoContianer');
let inputField = document.getElementById('inputField');

addToDoButton.addEventListener('click', function() {
  var paragraph = document.createElement('p');
  paragraph.classList.add('paragraph-styling');
  paragraph.innerText = inputField.value;
  toDoContianer.appendChild(paragraph);
  
  inputField.value = "";

  paragraph.addEventListener('click', function() {
    paragraph.style.textDecoration = 'line-through';
  });

  paragraph.addEventListener('dblClick', function() {
    toDoContianer.removeChild(paragraph);
  });
});