Adventure Mode-Bounty - Stuck, there is no exit

After completing the bounty or killing final boss, there is no exit. Trapped in room with no wavepoint or entrance to another level. Can’t do anything. When exited game and going back, lost all progress on the bounties completed. This happened twice and 2 different dungeons.

Did you try just Town Portal back to town? Certain bosses (like the Infernal Machine bosses) have no exit from their zone and you have to Town Portal to leave.

I have the exact same problem. I reach level 70, I killed everything, started the adventure chapter ( Act 1 ) and in some dungeons, there is no exit whatsoever, after killing bosses.
No door, no portal, no obelisk, no absolutely nothing.
The SOLE way you can leave that room is by quitting the game, which also erases all your progress and you have to do it all over again, over and over and over.

Any solution, please ?! I cannot finish Act 1 !

Use town portal (right on dpad). Or use quicker way and open map (down on dpad) and use either shoulder button to go to select new bounty in same act or select another act. No need to quit.

Now I want to know why I even have to explain this?