How to clear woocommerce checkout form after pageload

I am offering customers a repurchase on the order confirmed page. If they click the link they are sended directly to the checkout page. However, the form is then prefilled with the previous data. I would like to clear it, because the idea is one product(ticket) per person.

So far i have the following (and in the page source i can see the script is loaded):

function print_script() {

if (isset($_GET('extrapersoon')) && is_page(21560)){

    echo '<script>
window.addEventListener("load", function(){myFunction()};

function myFunction() {
add_action('wp_print_scripts', 'print_script');

I tried other triggers too, such as window.load but no result yet.