How to remove ‘hidden’ class [closed]

I am having trouble removing the ‘hidden’ class on my inputPlaceholder. I checked the console, and the hidden class remains after clicking the “allClearBtn.”

Here is my code:

const resultBox = document.querySelector("#result");
const inputPlaceholder = document.querySelector('.result-span')

function clearInput() {
  inputPlaceholder.classList.remove('hidden',);
}

numberBtns.forEach(function (number){
  number.addEventListener("click", function(){
    inputPlaceholder.classList.add('hidden');
    resultBox.innerHTML += number.innerHTML;
  });
});

I tried using classList.replace(), using a visible class which set my inputPlaceholder to “display:block”, but that did not work. I also made sure my clearInput function was being triggered by doing resultBox.textContent = ”, which did work.