Guild Wars 2

When first clearing the Nightmare Ender event, within the Tower of Nightmares, I was supposed to trigger the reward pop-up for the Antitoxin Injector back-item skin.

However, this pop-up did not trigger in the first or subsequent clearings of the story instance. Neither did the skin find its way into by inventory. Tried it on different characters, yet to no avail.

Any advise on what I might try?

Never mind! Much to my embarrassment, I took the wrong exit.