Qwest/Century Link - this was a notice to tell me my internet service was back up and running after an outage.  Courtesy call.

I recieved a call from this number at 3:15am and the caller id said "QUEST CORP". I didn't answer the phone as I never heard it ring but there it was on my caller id the next morning.

I've been getting call from this number every other night.  It always around 1~3am.  The person always hang up on one ring, I never get a chance to answer in middle of the night.  And it didn't even show the number on my caller ID since it was too short call.  I'm getting frustrated because I can't sleep because of this short call...
But after I talk to the phone company, I finally got number from *69.  But I don't know who is this...  It's been happening past 6 months and disturbing my sleep since then.