Text Field Not Showing in product page

Hi!

I've just started a promotion on my website for my birthday - but unfortunately at the exact same time an issue has occured that I'm not sure how to fix

I was wondering if there's anyway you can take a look at the issue and let me know how to fix it?

I've granted support access.

On the product page (/wp-admin/post.php?post=29180&action=edit) If you scroll down to the bottom then tick "Send a notification email to the customer? (Hitting save button will send the email)"

it will expand with a field to deliver the order

but the text field for "Message" is missing so I cannot deliver any orders :slight_frown:

http://i.imgur.com/EXVOZnp.png

I'm really stumped on how to debug this, and I'm concerned because I've already started promoting the website for my birthday and we are receiving quite a lot of traffic.

Any idea what I can to do fix this? Any help is really appreciated!
Thanks in advance