Bought wrong item, even though clicked on the correct item.

I meant to buy an Unidentifiable Shell from Auriana in Revenants Toll. I clicked on Unidentifiable Shell and it bought an Encrypted Tomestone instead (the first item in the list). I lost 300 tomestones of poetics and now have an item i don't want. I submitted an in-game bug report, but how do I get back my tomes?

Unfortunately, I don't think you can do anything about this kind of thing. Sometimes accidents happen, but at least Poetics are easy to come by.