F1 Visa dropbox Chennai VAC - processing time

Hi all,
I submitted my passport for F1 visa at the Kochi dropoff location part of the Chennai VAC on June 6th. It has been 21 days since and I haven’t received any status updates. Status of the application is still shown as ‘Application Received.’

Could you anyone advice on whether this delay is normal? I heard from other F1 dropbox candidates that it only took 7-10 days to get back their passports.

Thanks in advance for your help!