HDFC Bank — haven't received hdfc fastag

I paid for hdfc fast tag on 4th of september 2019 and i still haven't recieved the rfid tag which was supposed to be sent to my place of work/residential address. I have no idea where the rfid tag is and i've not recieved any communication from the bank saying it has been shipped / is out for delivery. I've called the customer care atleast 10 times but nobody answers my calls. They don't even have a email id for me to drop my queries. I have no clue on how i can reach out to them.