A bugger called me at 3 something in the midnight - and welcomed me with silent phone call.

I slept and 30 minutes later she called again - with the same silence in the phone.

I waited this time - within 10 minutes she called again and in silence again.

I couldn't sleep after that. (FYI, once I'm awaken, it'll be hard for me to sleep again)

About 15 minutes later, I used my VOIP service and called her (which will show "Withheld" number on the recipient's phone)

She answered and immediately, I greeted her with some long breathing sound, and occasionally greeted her with the breathless "Hello".

She said "Hello" for a few times (that's how I know her gender) and after that, she hang up the phone.

After I woke up at 10 something this morning, I've been giving her hourly morning call to see if she'll answer again.

Good luck, you've just annoyed the wrong person.