Hi. All our hamsters have always moved into the Rodipet labyrinth houses
Robo, Syrians.
They can take a couple of days to decide to move in, depending on where they were nesting before and depending how stressed they are after the changes to the cage. The other thing I've found is the temptation to keep taking the roof off can make them bolt and move out again if you do it too much when they've first moved in!
Where was she nesting before? I usually put the new lab house in the same place as the previous nesting area, over the top of it and put the old nest in the front left hand side room. And a litter tray in the middle back section. Mostly those are the two sections they have used. They have all nested in that front left compartment - its the darkest and next to the middle back compartment. One Syrian decided to have his toilet in a different compartment further away.
I think she maybe just sounds a bit skitty. Do you have a photo of the cage with the house in? Is it blocking something else maybe? Or a bit wobbly? They don't stand on the substrate very well and can sink so either need supporting on little legs or instead have them as a kind of subterranean house so it sits on the base of the cage (I the just put a little bit of substrate inside it so it's not bare cage floor). And the substrate around it so the roof is only just above the substrate - then scoop out abit of substrate near the entrance door.
And yes put some food in it as Luna says - a smelly treat like cheese or cucumber ih the main nesting compartment and a bit of hamster mix like a hoard in another compartment.
Did you do a full cage clean before adding the house? That can stress them and make them skitty especially if the old nest and hoard are gone. Best to just spot clean mainly and not clean everything at the same time. I always leave the nest and hoard as well but prune the bottom half of the hoard eventually when I do change the substrate (usually not for a good few months with spot cleaning and a litter tray). Sorry if you know all that already!
I had one syrian who had another house in his cage as a kind of hideout and he spent almost a week moving between that and the labyrinth house deciding which one to nest in but settled in the labyrinth house
. If there's no other house they usually move straight in! But if she is skitty then under the shelf may feel like a safe familiar place.
Putting the labyrinth house on little legs can work well (or some support under the sides) as then there is substrate under it and they can burrow down and bury hoards - but it works both ways.