Tags in subject line

Id like to show a subject line of:

Order #{order_number}: Blah Blah Blah


Currently the tag is not passing in subject line, though it does in body.

Can you help me make that happen?

Hello,

You can edit
administrator/components/com_awocoupon/helpers/estore/estoregiftcerthandler.php

Search for $subject, you can use str_replace to pass what you need to. See $message for example.