why .innerHTML not working in sololearn

Question

if i try something like: document.getElementById(id).innerHTML = 'some str'
its return error. what's the problem?

Answer 1

I think because your js code runs before the actual DOM even exist.

try this :

window.onload = () => {
// your code goes here
}

Answer 2

What is the I'd there? Is it in proper way?
Where is actual code? Showing that may help to identify..!!!!