"addEventListener" is not working on this...

Question

If you know why tell me...

Answer 1

You need to ensure that the html is loaded before you try to get an html element in Javascript.

Put all your Javascript inside window.onload:
window.onload = () => {
// your code
}

Answer 2

Can you share the code where you're experiencing the error?

Answer 3

https://code.sololearn.com/Wno9GNgl2Yh0/?ref=app

here is the code...