coop up
coop somebody/something up
usually passive to keep a person or an animal inside a building or in a small space I’ve been cooped up in that office all day.
e.g.
Not quite. It's just dozing while it's cooped up in there. いやちょっと違う うつらうつらして籠もってるだけだ (/yupeco/『ゴールデンカムイ』8話)