Return to Same Page after Registration

mepr_return_to_page

function mepr_cust_registration_input($product_id) {
  global $post;

  $input_str = "<input type='hidden' name='mepr_cust_current_page_id' id='mepr_cust_current_page_id' value='{$post->ID}'/>";
  echo $input_str;
}
add_action('mepr-checkout-before-submit', 'mepr_cust_registration_input');
function mper_cust_thankyou_url_params($url, $args) {
  if (isset($_REQUEST['mepr_cust_current_page_id']) && $_REQUEST['mepr_cust_current_page_id']) {
    $param_str = http_build_query($args);
    $url = get_permalink($_REQUEST['mepr_cust_current_page_id']);

    if(strpos($url, '?')) {
      $url .= '&';
    } else {
      $url .= '?';
    }

    $url .= $param_str;
  }

  return $url;
}
add_filter('mepr-thankyou-page-url', 'mper_cust_thankyou_url_params', 10, 2);