Friend didn't get the playtest email

Hello, I signed up for the playtest with two of my friends and according to them they both signed up correctly and in the same way and using the referral code but only one of them received the email with the info to download the game, I was wondering if there was any reason why or if anyone else had an issue like this with the playtest. I was hoping there was a support line I could reach out to but couldn't find anything