Hi everyone. So i just turned in my SIR for Columbia!

How should I apply for housing now? I went to the welcome page and got directed to this link
https://housing.columbia.edu/StarPor...wawyQrB1jPheWw
The instructions say: If you are an incoming New Student who has not previously applied for housing, please login under Account Login using your PID (C123456789) and Date of Birth (mm/dd/yyyy).
So where should I find my PID? and there's no place to log in using date of birth.....
Help!!