WooCommerce email headlines cannot be customized

Hi:

I have changed the email headlines in Woo settings for the “completed order” and the “procesing order.” I have also copied the php files for each into a woo “…woocommerce/ emails” directory and in “ecommerce/emails/plain” into both the Enfold and Enfold Child, (because just the child didn’t work,) and it doesn’t change the headlines in the emails.

How can I get this to work—the client wants the completed order to state that the order has shipped. And I need to change the order processing headline too.

Thank you.

Michael Blair