Fatal Error, No Emails Going Out

We've been using Email Customizer on our site with no problems for over a year. Recently, however, we realized that customers were not getting their order emails and neither were we. When I go into the Email Customizer, this is the error code that I am getting:

"Fatal error: Call to undefined method WC_Order::get_edit_order_url() in /home/reviewsite/public_html/wp-content/plugins/woocommerce-email-control/templates/emails/woocommerce/email-order-details.php on line 29"

It looks like this directly relates to the Email Customizer plugin, unless I'm missing something.

Please help!