How does the spend 10 get 5 work?



I have bough some gigs now and spent around 20$ but how can I get the bonus which is 10$???


Reply to @radjaseotea: No I mean about the Fiverr official offer it’s in the header of the website " Spend $10 and get $5 back! valid until 04 Jan 05:00 " and also I received an email from fiverr