Hi, Michelle 

Thanks for reaching out to us

Can you please try this:

If you go to Amelia settings > Payment settings > And when you activate WooCommerce, scroll down to  Set MetaData and Description :

Try to customize the text like this :  and add the placeholder of number of persons, like on the screenshot,

and of course, for the Custom fields, you can also make your own label, and add the two dots ":"

And add placeholder for every custom field that you need.

You can copy custom field placeholders from the Email Notification section.

Let me know if that helped? Thank you