A 10% discount is available for the Tick Data Suite during the 2018 Christmas period.
In order to take advantage, enter coupon code TDS-XMAS-18 in the order form when purchasing a new license.
The coupon code is valid until the end of the year (the end of 2018, of course).
! The coupon code you entered is invalid. If you have questions about this, please contact the publisher.
As mentioned in the article, the coupon code only works with new license purchases.
I guess you tried to use it with the update package and indeed it does not work in that case.