unrelated

The two incidents are completely unrelated, although they happened on the same day.

(Chinese) 尽管这两起事件发生在同一天，但它们完全没有关系。

She shares the same last name as the famous actor, but they are unrelated.

(Chinese) 她和那位著名演员姓氏相同，但他们没有亲戚关系。