共用ロッカーの日またぎ利用はできません。 を英語に訳すと？

Overnight usage of shared lockers is prohibited. If a locker is found in use overnight, its contents will be inspected, and the user will be notified.

もし「日またぎ利用」ではなくて、「連続日数の利用」というふうに表現するなら、こんな感じです。

Usage of shared lockers for multiple consecutive days is prohibited. If a locker remains in use for more than one day, its contents will be inspected, and the user will be notified.