Ideas
I'm having the same issue. I reported this case via the cases system and didn't seem to get a clear response on that EA/DICE was even documenting this issue, despite them saying they were, which is extremely concerning. I have the Phantom Edition of the game, and so I would have assumed after completing my challenges that I would have gotten the items, but I never received them and got stuck on tier 4 of the Pro Pass.
This definitely turns me away from buying battlepasses in the future, considering that I have had so many issues on this game with this new pass system (both the pro-pass, California pass, and even hearing people still not receiving their instant rewards when purchasing the battlepass).
I really hope this is fixed and that DICE/EA are actually working to provide the items to the people who paid and played for them and did everything. Just extremely frustrating in general though...