Finally received a paper letter in mail about the deferred decision - it actually said the application was denied because Chase suspected it was fraudulently applied, i.e. SSN being stolen to commit fraud. It does say if you are indeed the applicant, please contact Chase.

I suspect this is because the multiple security breaches in the past 6 to 9 months. We were told by CapOne, AMEX and of course Chase that our SSN / Personal Data were found on Dark Web since over a years ago, and a couple more time the past several months. Chase system might very well compare the SSN on application with those exposed on Dark Web.

In any case, once we called and verified applicant ID, the decision process was fairly quick, though to expedite the card the call still needed to be transferred to a Customer Service Rep from the Fraud Dept Rep (who also had power to make approval decision - most likely let the system generate a result per the info on the application) in order to handle the expedited delivery.