Sisters of Garukhan event bugged. (Act 2)

I did the Sisters of Garukhan event in Act2, in the Spires of Deshar. World map states that I completed it and got +10% lightning resistance. But I never received an item to get that lightning resistance and when I go in my stats I have the same 17% Lightning resistance that I had before I did the event.
I should have 27% after but it's still 17%.