Citadel Completion Bug?

So I was clearing the stone citadel with a friend and we have finished the map rares and boss, afterwards we start the breach that was located inside the map and things are going smoothly until our server ping skyrockets and we are unable to move.

After waiting for awhile we both decided to close the game and reopen, after we did, we found that the map had been failed, the fragments and other loot from the map are gone and the exp we gained during that whole ordeal is null.

Anyone else had this happen? And can we fix this? those citadels are NOT easy to find and its frustrating to have this happen...