I also haven't received the helmet despite most of my friends have - we all play on the PC Steam version of the game.
I've been playing this game on and off all week doing various races and game modes, refreshed my inbox many of times. Even went to the extent of disconnecting my internet, booting the game up in offline mode, then re-connecting my internet to see if it would update my mailbox but still - nothing.
I entered a live-chat with an EA support representative yesterday regarding the issue and they couldn't assist me, they claimed they made a bug report with a written up transcript on my problem and said it would be under the my "cases" page with updates on the scenario but there is nothing on there regarding it whatsoever except the log of the initial conversation between me and the EA customer support team member. They also pointed me towards coming here with a link to check if other players were having the same issue, I was told to upvote posts if I could find any.
I've attached some images below showing my empty mailbox, and the helmets that are available to me on the driver wear customisation menu - there is no Max Verstappen Miami Edition GP helmet anywhere to be seen.
This is the second time I've had to visit here in the past three weeks regarding missing content, first it was the Community Canada Grand Prix event, and now this helmet, I'm getting extremely irritated with EA and/or Codemasters at this point.
