Old inoperative PF - how to withdraw - ex-employer refusing attestation

I have old pf account of year 2011-2012 during which UAN no was not there. I have approached ex-employer multiple times and send physical form to get their attestation but they are refusing for it and inform me to take procedure online. I don't have UAN number nor my ex-employer is providing me.The account is inoperative since 6 years.Please guide me how i can close this account and withdraw funds.

Dear Anony,
When you login to your UAN on unified portal, check if old employer is showing in "Service History" under the View Tab. In case not, you can add the old PF by clicking on "transfer request" under the "online services" tab.
Regards
Rahul Chhabra