A wrong-number call — a phone call dialed to the wrong number (equivalent to 'wrong number').
先ほど間違い電話がかかってきて、事情を説明した。
A wrong-number call came in earlier and I explained the situation.
相手が年配の方だと、間違い電話でも丁寧に対応したい。
If the caller is an elderly person, you'd want to respond politely even if it's a wrong number.
新しい番号を知らせたら間違い電話が減った。
After notifying people of my new number, wrong-number calls decreased.