It is always a good idea to name the expansion you are discussing. Did you check /claim to see if it was listed? Expansion items must be claimed unlike other games where they are ingame mailed to you.
If you are reffering to PoP, you won't get any of the items, except for the pre-order item. until the expansion goes live.
It may be a good plan to have a couple of your guild members walk you through the exact steps they received the items you appear to be missing. You are still not clear which expansion you are referring to; the last expansion most folks are playing or the soon to be released expansion which only beta testers are playing.
The only things you should be able to claim right now are the boost to level 100 for adventure and the clockwork calamity illusion. Everything else will only be available after the expansion goes live.
Dude and Prissetta are right, there are only two items you can claim right now; the rest are available once the expansion launches (currently scheduled for 11/28). It's also possible you are seeing some of the PoP beta testing rewards, which are claimable on Live servers once you earn them (the Djinn illusion mount and the clockwork familiar are two I can think of offhand).
If you pre-ordered PoP (it appears that that is your intent) then either the order did not complete (did you get a confirmation from DBG?) or, if you have more than one account perhaps you accidentally upgraded the wrong account. Either way, nobody on these forums or on Discord can help you in any meaningful way. You will have to file a petition for help from Customer Service.
I like your sig Sven, a shiny dislodger or some way of being able to remove a shiny prior to turning collection in would be nice.
I keep hoping! Anything that is addable should be removable. Granted, it really isn't quite that simple, I understand that, but who said all desires should be simple? I wouldn't even mind if the removed shinies were made heirloom! The idea here is not to sell them or even trade them to a 2nd account, but to allow the removed shinies to be used by another character of your own. Devs! Make it happen!