Set the default status of new orders to completed

After the successful payment, the woocommerce_payment_complete hook is fired. So you can use it to programmatically change every order’s status to Completed after payment.

Please add this PHP snippet to your WordPress / WooCommerce site:

add_action( 'woocommerce_payment_complete', 'bmwp_set_completed_for_paid_orders' );

function bmwp_set_completed_for_paid_orders( $order_id ) {

    $order = wc_get_order( $order_id );
    $order->update_status( 'completed' );
    
}