Vaal Ruins loses the portal back to host map.

Vaal Ruins can sometimes lose the portal back to the host map. I did not die in Atziri's Temple but after exiting the Temple the portal back to the host map was gone and I was forced to return to hideout. The portals back to the map were no longer there. This has happened twice. The map then counts as a failure and as one of the occasions was in the 15+ Corruption Nexus it was quite frustrating.