I'm trying to determine which coupons are being used. For example I have Company A which gets a coupon ("A" at 10%) and Company B, who also get a coupon ("B" at 10%). The service is the same (Service X) but the end result is slightly different (in my case, a photography studio, they both get a single image, but Company A is shot against white and B is shot against grey). If someone from Company A and B book on the same day, I need to know which session is which. I was looking for a shortcode in the notification (e.g. %COUPON% so I can easily tell which client is which as the amount they pay is identical (both get a 10% price reduction). If not a notification is there anywhere else on the system I can determine which coupon was used by whom? The appointment info just says "DISCOUNT" but that doesn't help me know which coupon was used.

Yes, I had to use a custom field. It's an extra step that really shouldn't be necessary - the system knows the client used Coupon A and all I need to do is to put that information in the email. Hopefully you'll consider this as a future improvement. For now, the need to use the Coupon (so the price can be adjusted) and then they need to tell me which company they belong to (even though the Coupon is specific to a company).