insert promo code into a database via node.js

can you help me please i'm stuck with this problem

i want to send to database a promo code and in the same time send an email with message and promo code to the one is register with us

here is my code i use http://www.mediafire.com/file/j0bw63u6ba6gs5c/mailer.js

and here is the error i got http://www.mediafire.com/file/1xp9yqc2nrvuxi7/error

via Firas Abu Fares