Dalaran Adventure rewarded me without completing the chapter

Technical Support
1

Did 2 runs with the Shaman on chapter two,both never got to the last boss, second run got to 6th, first run got to 3rd, got beaten however I still got the 3 pack reward…

https://i.imgur.com/rtMEmuX.jpg

https://i.imgur.com/J8KZrZY.jpg

https://i.imgur.com/cG0fdZl.jpg

Kinda ruined the experience there Blizzard…

2

The reward is given when you get to chapter 5 in a run. If you hover over the little chest before starting a run it tells you this.