If you offer a 100% discount to a series, in the register, the customer will need to enter the promotion code and hit Apply.

As soon as they hit Apply, the transaction completes and the customer will be credited for that series as a comp. Occasionally, customers will enter in their credit card information and enter the code but bypass clicking Apply. In this case, the customer will be charged the normal price. They must select Apply in order for the promotion to work

NOTE - Comping Series and Contracts do not remove the 'New' status from the customer, allowing them to benefit from Series/Contracts restricted to New customers. A customer is only no longer considered New whenever they purchase a Series or Contract that does not allow them to remain new on purchase.