When they fly into rooms in this house we just leave a window open and turn off the light and they go out. (We had one roosting in a wardrobe once. Maybe there were moths in there!) You may find, as it's been seen in the office, that will work and it will go. It must have got in somehow and there's no food inside so it probably doesn't want to be there!
We occasionally find one that's crawling on the carpet. We just pick it up firmly but gently as you would a small bird and put it out.
Can't think it's roosting and making a home for itself but if a bats do settle in it's illegal to disturb the site. Only a person who is licensed to handle bats can deal with them or handle them, and arrange their being moved, (Yes, I know, but I don't count rescuing one off the carpet as 'dealing' or handling'!)