MarketPress Invoice Add-on cubblers my theme

Hello WPMU,

WordPress Multi-Site: 4.5.3

MarketPress: version 3.1.1

Website: http://bluegemini.ca/store/

I’ve recently activated the Invoice PDF add-on and ran into an issue with the add-on cubblering my theme. It happens when you’ve finished the Guest Checkout process and you are taken to the Order Status screen. There is an Invoice button that now displays which is awesome for the customer, however, my theme pays the price. Could you please let me know what might be going please? Please see attached.

Thank you,

Tin