This is the email amazon sent me
"Thank you for purchasing from Amazon.com. Order 113-4299253-7923412 has earned you a promotional reward which we have added to your account. This reward can be applied to your next eligible order.
Promotion details:
Additional information on this offer can be found here.
Thank you for treating someone to an Amazon.com Gift Card. Now we're treating you to a $15 promotional credit automatically applied to your account, and good for eligible products sold by Amazon.com.
This reward will expire on February 15, 2018. For more information, please read our Terms and Conditions.
Thanks again for shopping with us.
Amazon.com"
sorry that i have no direction for the public. The add just there on amazon's page that said that this promotion is good for amazon family members (which is included in prime) so i just clicked on it. But I will search a little and if i come up with anything I will let everyone know
sorry again!