How may I help you?

Time is 11.45pm and my cell phone rings...

Me: Hello?
Caller: Hello!
Me: (does not recognise the voice) Hello?
Caller: Hello!
Me: (slightly annoyed) Who is this?
Caller: This is me...
Me: (very annoyed) You've got the wrong number.
Caller: Oh okay...
Me: (hangs up)