I was cut off.
→전화가 끊겼어.

〔예문〕

A:The battery in the celluar phone wemt dead last night on the subway.
  So I was speaking with my girlfriend but I was cut off.
  어제저녁 지하철역에서 핸드폰밧데리가 나갔어.
  그래서 여자친구랑얘기하다가 전화가 끊겟어.

B:Oh, man, that's too bad. Hope you get a recharged battery.
  저런.베터리 충전시켜.