You can access your invoice online, under the account section:
Step 1: Log in to the website and open orders, located under the account menu
Step 2: Select the past orders section and find the order you want the invoice for
Step 3: Select order details and on the next screen, choose to either download a PDF invoice or view it online.
If the invoice you need was prior to November 2017 please contact us and we'll happily email a copy to you.