A package has arrived for you at the superintendent's office. Please come pick it up when you have a minute.
この場合、次のような言い方ができますよ。
ーA package has arrived for you at the superintendent's office. Please come pick it up when you have a minute.
「管理人室に荷物が届いているので、都合の良い時に取りに来てください」superintendent's office「管理人室」
to come pick ... up で「…を取りにくる」
ご参考まで！
カナダ 
