thank you page changes

it appears that apparently on functions.php this causes the issue of breaakdown and of the 3 errors reported above.
add_action( ‘woocommerce_thankyou’, ‘custom_woocommerce_auto_complete_order’ );

function custom_woocommerce_auto_complete_order( $order_id ) {
if ( ! $order_id ) {
return;
}

$order = wc_get_order( $order_id );

if ( $order && ‘cod’ === $order->get_payment_method() ) {
$order->update_status( ‘completed’ );
}
}
i am struggling to find something like this but with no success.
any idea what to apply in order to accomplish automatic set of order to completed status?
thanks in advance!

hi, i have eliminated all errors.
I think that still the re order does not work well yet.
1. this is the order created with reorder with the customer not logged out after initial order. https://i.imgur.com/RgaB1wT.jpg it is normal.

2. this is the order created with reorder with the customer having logged out and then logged in again.https://i.imgur.com/zMeTxlI.jpg. the store has not been selected as you can see on highlighted. the admin must select from drop down :).
so the re order is not completely applied if the customer has logged out and then logged in. The re order is completely applied if the customer has not logged out at all.
I have also enabled the woodmart theme, not the child, so all the functions.php settngs do not apply now. But still the issue persists and only on re order after customer has logged out and logged in again.
Any idea please? it is really important.
Thank you