[In case this is needed info to help this.. I use Windows 8 (8.1?) and usually Firefox or Chrome.] (I also tried to find this topic elsewhere, but didn't see anyone else with this issue.)
I have been doing an rp group for a few years now. Last year, I created an avi for it, but instead of just posting what I created in the Wardrobe as part of my post, I like to have my actual avi represent my character for the duration of the event. That character was wearing the item Peacockulous Wig and Pewter Time Flies Cuff. I know for a fact I owned these items. The wig I loved and the Cuff our team decided for each of our characters to have one.
This time when I was creating an updated version of this character, I tried to 'Wear on Site' but my avi was suddenly bald. I thought it was really weird. I was Certain I had that item. But I had plenty of steamworks tokens and bought another wig (even though the wig is a bit expensive, I like it). Today, though, I noticed the Cuff was gone too (not showing up).
In this case, I consider once a coincidence, but twice...? And both Steamwork items..?
https://subeta.net/isearch.php Account search for the items to see if they somehow got moved somewhere else first. If you can't find them, then I would file a ticket and see if an admin can find out what happened to it. For missing items, filing a ticket is the best course of action.