HDFC Bank Fastag — hdfc fastag not delivered

Hi,
I applied for HDFC fastag on 11 Nov., 2019 and got reference number HFR358449.
After payment of RS 500, the receipt mentioned that the fastag will be delivered within 7 days. But I did not received it. I also tried to contact the customer care, but the toll free number is not working, so I can't contact the concerned authority.
I expect that the concerned authority will work professionally