Same for me Woody051.
I play on Steam and I haven't received a booster since Day 3 or 4 after release. My mail box autodeleted all my messages and yesterday I got a "BF6 friday something hangout" and it's autodeleted today...
I think (as others do too) that the ingame mailbox is bugged and source to all our problems.
I just wish EA could fix this ASAP! Loads of items and XP boosts are missing, not a good start for this game imho.
While they are at it, they could fix putting me into games that ends with a loss 30 seconds after I joined! Seems they like to lower my already low rating LOL. 🤪