Thanks for your info
I emailed buffalo for my AOR.
I've been in Canada from 2002-2009 (international college, university and master), 2010-present.
So I have my client ID since long time ago.
I hired a immigration consultant to deal with my immigration case. (under family sponsorship class)
They havn't received anything (except DM for sponsorship) since they mailed my file.
I emailed bufallo in sept, they claimed that they sent my AOR through email on april 3rd (also noted in GCMS notes).
But apparently I had my file number only after I email buffalo to claim it by myself.