Fatal Error

“Sorry but your code causes a “fatal error”, so it is not applied!
Please, check the code and try again.

this is the code that I entered. It is a php code to implement WooCommerce with Zoom webinars. Now I am locked our my my admin page as well.

“The site is experiencing technical difficulties. Please check your site admin email inbox for instructions.” No email has been received.

// add hidden field in order after checkout
add_action( ‘woocommerce_checkout_before_customer_details’, ‘my_custom_checkout_hidden_field’, 10, 1 );
function my_custom_checkout_hidden_field( $checkout ) {
foreach ( WC()->cart->get_cart() as $cart_item ) {
$product = $cart_item[‘data’];
if(!empty($product)){
$webinar_id = $product->get_attribute( ‘webinar_id’ );
// Output the hidden field
echo ‘<div id=”user_link_hidden_checkout_field”>
<input type=”hidden” class=”input-hidden” name=”webinar_id” id=”webinar_id” value=”‘ . $webinar_id . ‘”>
</div>’;
}
}
}
// save hidden field in the order
add_action( ‘woocommerce_checkout_update_order_meta’, ‘save_custom_checkout_hidden_field’, 10, 1 );
function save_custom_checkout_hidden_field( $order_id ) {
if ( ! empty( $_POST[‘webinar_id’] ) )
update_post_meta( $order_id, ‘_webinar_id’, sanitize_text_field( $_POST[‘webinar_id’] ) );
}
//only 1 prod in cart for WooC
add_filter( ‘woocommerce_add_to_cart_validation’, ‘bbloomer_only_one_in_cart’, 99, 2 );
function bbloomer_only_one_in_cart( $passed, $added_product_id ) {
// empty cart first: new item will replace previous
wc_empty_cart();
return $passed;
}

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