Why is this timing function getting a typeError?

Question

The timer stops when the mouse hovers over a (.typing) item and the timer resumes when the mouse leaves. That works, but I wanted to remove two classes from separate id's when their respective setTimeout function hits 0.

Heres the code:

let dhaTimeout = {
  id: null,
  startTime: 0,
  remainingTime: 5000,
  isPaused: false
}
let stackTimeout = {
  id: null,
  startTime: 0,
  remainingTime: 10000,
  isPaused: false
}

function startTimeout(timeout, elementId){
  if(timeout.isPaused){
    timeout.isPaused = false;
    timeout.startTime = Date.now();
    timeout.id = setTimeout(() => {
      const element = document.getElementById(elementId)
      if(element){
        element.classList.remove("gone")  
      } else { 
        console.log(`Element not found, ${elementId}`)
      }
    }, timeout.remainingTime)
  } else{
      timeout.startTime = Date.now()
      timeout.id = setTimeout(() => {
        const element = document.getElementById(elementId)
        element.classList.remove("gone")}, timeout.remainingTime)
    }
  }
function pauseTimeout(timeout){
  if(!timeout.isPaused && timeout.id){
    clearTimeout(timeout.id)
    timeout.isPaused = true;
    timeout.remainingTime = timeout.remainingTime - (Date.now() - timeout.startTime)
    timeout.id = null
  }
}

function onMouseEnter(){
  pauseTimeout(stackTimeout)
  pauseTimeout(dhaTimeout)
}

function onMouseLeave(){
  startTimeout(stackTimeout)
  startTimeout(dhaTimeout)
}

document.addEventListener('DOMContentLoaded', function() {
  document.querySelectorAll(".typing").forEach(element => {
    element.addEventListener('mouseenter', onMouseEnter)
    element.addEventListener('mouseleave', onMouseLeave)
  })
})

startTimeout(stackTimeout, 'full-stack')
startTimeout(dhaTimeout, 'dha')

I'm getting a typeError when the startTimeout function is called for the second time, saying can't read classList when it's null. So I logged the element to see if its there but its not finding it.. but I have nothing removing the individual element so it's not making sense to me how it's not finding the element, maybe the class but the element being gone? I didn't think the html code was necessary as its 3 p elements, first two with the 'typing' class and last two with the 'gone' class. id of 'dha' for the second p and 'full-stack' for the third.

I've tried to add a separate if else for the failure of finding the element to find it again somehow but that lead nowhere.