Give it time, I ordered June 7th, delivery was made yesterday afternoon, and code was sent via email at 9:30pm. Setup was straightforward, and you can install the chromecast device first without the need of the activation code. Once you get your code, fire up the Stadia app on your phone, link account and enter code, then choose your username and after that it's just a case of follow the instructions to get it all working..very easy..
Kudos appreciated if deserved.