My husband and I have been playing through the Deeds of a Champion content following the VoH expansion story. We’re several steps into this in Kurast Undercity. I had just found Sihek in the Council Chamber when he had gone to inform Ormus and the rest of the council he is infected/has failed to find a cure. The dialog had completed - I talked to Ormus (who told him he would now be Undercity Guardian), talked again to Sihek (who expressed surprise at the outcome). Quest completed.
I expected to have the next quest in the chain, but nothing happened. I opened the map and found that all my existing quests had disappeared. I opened my journal, and all the quests were gone - this includes all of the different quest types: yellow and purple main content quests, including the Echo of Hatred Quest, and all side quests that I had. I logged out and back into the game (exited all the way to Desktop and re-entered via BNet) and the side quest exclamation marks were present in Kurast again, but the main quest is now gone and I have not found a way to access it or add it back again. Logged out on my PC and logged in on another computer to see if it was a local issue but appears to be account and/or character. Decided to complete the side quest that is one of the three requirements of the Deeds questline since I had already done the other 2 requirements (several rounds of Undercity things with Sihek and the required Stronghold). Completed that questline in our group of two, he got credit in the Deeds questline, I simply got completion credit for the side quest.
Tried doing a random Undercity run since we’d unlocked that just to see if it would help, nothing changed. Scanned the files to look for possible corrupted/broken files that might need repaired and BNet did not find anything. So now I’m stuck, unable to progress to unlock the rest of the endgame content and very disheartened.