Hello,
i tested on 2 different servers with 2-3 domains (top and sub domain) and got everytime the same mail template error.
For example I installed actual PrestaShop 1.7.0.5 on php 7.2. After deleting /install I go to demo shop and made an order, with standard template.
After the test-order I got this attached screenshot.
The variables like "FIRSTNAME" are not "HALLO Roberto Smith" for example.
What is wrong?