If you ever need to change the order status from php here is how to do it.

[php]
$order = new WC_Order($order_id);

if (!empty($order)) {
$order->update_status( 'completed' );
}
[/php]

Possible values: processing, on-hold, cancelled, completed

This is from woocommerce/includes/abstracts/abstract-wc-order.php

Disclaimer: The content in this post is for educational purposes only. Always remember to take a backup before doing any of the suggested steps just to be on the safe side.
Referral Note: When you purchase through a referral link (if any) on this page, we may earn a commission.
If you're feeling thankful, you can buy me a coffee or a beer