Merchants: Wrong item appears in inventory

[Dr4z3r]

Bought 2 Words of Absorption just now from Shady Swashbuckler. Paid the money, and received 1 Velishoul's Tome Pg. 75.

Sold it back, and it appeared as a second instance of 1 Velishoul's Tome pg. 75 in the merchant's inventory.

Closed & re-opened the window, and it showed two Words of Absorption again, and I tried buying them again.

This time it was Words of the Suffering.

Only 5pp or so down the drain, but this is really awkward...