HDFC Bank — fastag not received

Address:

560035

I applied for fastag from HDFC bank on 24th of November. Money got deducted from my account.
HDFC bank has sent the fastag customer ID and wallet ID. However they haven't sent the physical fastag so far.
Their fastag customer care number is unanswered. And the HDFC Bank customer care say they don't deal with fastag.
Being such a big enterprise, how can they let down their customers after taking the money. They have to give us a tracking number to track the status of the fastag.