Simulacrum portals disappeared?

Finally finished putting together my very first Simulacrum. Pop it in the Realm Gate, the portals open, and I realise I meant to swap to a Thawing charm first.

I open my stash, fish it out, and... the portals have disappeared.

I understand that instances will close after 8 minutes or more, but this took less than 60 seconds.

The Simulacrum's gone as well, of course, so that just screwed me over big time. Please fix this. I know it's Early Access, but still... this will be the second time I've lost expensive fragments I can only afford to earn, rather than just buy, and it really sucks the life out of the game.

Thanks, and keep up the good work otherwise!