a while back, i bought and and added them to my inventory. i didn't try to use them until recently, so i didn't notice that, despite definitely getting confirmation that they were added to my wardrobe, they're not showing up when I filter to "Only show items you own".
Sometimes you need to wait a few minutes to let the cache catch up. Be sure to do an account search to be absolutely sure as well.
thing is, i bought these a few weeks ago. i've tried to apply it even though it's not showing up as an item that i have in my wardrobe but it's not showing up at all.
Yikes! I am sorry. :( Hopefully this can be looked into! Good luck!
quick update: not turning up in account search or anything, and i definitely didn't delete them or anything because i used the "add to wardrobe" button that shows up on the screen that confirms that you've purchased something, not through my inventory. dunno if that's an important detail or not!!
I ran into a similar problem with a vanishing item from Skelly Manor and an add to collection button - doesn't seem to a common issue because you're the only other person I've seen who encountered it. I sent in a ticket asking if it could be investigated to work out where it had gone, and the team got it sorted for me. I know that's not particularly useful for you but at least you know you're not the only one!