Often dogs don't know WHERE to go, in a new place.
So, take them out every 3 hrs and treat/praise with proper elimation.
Also, keep the areas of the apt your not in, closed.
Keep the dog with you, and if you see the nose down, take it out.
This should pass as the dog gets more settled.
We travel a lot with our dogs, and we keep them with us in motel rooms, with closets, bathrooms shut.
When they act like they are sniffing, we take them out.
Also, extra exercise with your b will help.
Good luck