How do you Redeem a GIFT CODE EGC BUNDLE4 AOS VAR?

I purchased a Apple Watch last November and it supposedly came with a $70 bonus. I received a receipt for the $70 bonus (as well as the receipt for the watch which was minus the $70 bonus) The bonus receipt shows the purchase of a product number and a web order number. I have tried to redeem the $70 while purchasing a new Macbook but the receipt doesn't clearly have a 'code number' and the reference numbers on it just don't work. It simply says 'GIFT CODE EGC BUNDLE4 AOS VAR' under the description field.

How do I redeem this??