In my wardrobe, I have 51 Steamworks Trinkets, and 49 Lounge Trinkets, but for some reason, when I go to buy even the cheapest items in the event shops, it says I don't have enough trinkets. Anyone know anything about this?

You have to turn them in with the link at the top of the shop pages.

Oh, I didn't notice that! Thank you!

You are welcome!