Quest reward bug

I completed the Enemy at the Gate quest with cruel difficulty and I went back to the city to reclaim my reward, as I talked to Tarkleigh and opened the reward screen I get disconnected from the game because I minimized it to read about different gems. This has happened to me before, but usually when you log back in you can just talk to the guy again and claim the reward.
However not this time, I completed the quest and did not get anything for it. Tarkleigh doesn't have the chat option that would let me get the prize. Really wanted that spell totem gem.

Hope this helps and I'm hoping to get the gem.