After you download the code, got to the tower, go to the postmaster. That is where mine were. But, you can also get more at the special deliveries shop.

Also check and see if you have downloaded the expansion pass and collectors content.

Go to postmaster. If not there try the special deliveries shop. However at special deliveries you have to pay glimmer because you should've gotten it for free at postmaster. But glitches are bitches.