WHO AM I?

This is a personal kung-an I got from Zen Master Seung Sahn:-
Long time ago in China, Seventh Patriarch visited Sixth Patriarch.
"Who are you?"
7th Patriarch only don't know, for 7 years.
BOOM! Got enlightenment, attained this don't know - nothing at all.

Who are you?

You don't understand.
Only don't know, always, everywhere.
Then some time you will attain this don't know, then attain everything.
OK?

He is asking me the same way that the 6th Patriarch asked the 7th. I have no answer for him and he knows that I don't understand. So, I am supposed to "don't know, always, everywhere"...until one day I attain it. So... who am I?