Open a ticket. You should get credit within 72 hours, often after 24 hours.
This has also happened to me on two purchases to Walmart the passed two weeks. One purchase I was supposed to receive 15.65 and the other purchase 38.05. Plus, bonuses for the items purchased. I have opened 4 tickets and received nothing. I have even submitted pics of receipts and screen shots of the amount I am supposed to receive!
Nothing has been updated... I haven't even received my bonuses for over 3 products I have bought... Its so frustrating I've spent all this money and get nothing for it.