HDFC Bank — fastag process error after payment accepted

Address:

560035

Hello,
My Fastag application when through till I made the payment of Rs 500 and received an SMS message as well, and then the website had an error.

Now I am not sure if the who process is complete and also, the phone number provided :[protected] is always busy for the past few hours. No one responds.

My application # is : HFR537314