Happened to me a couple of days ago when I was traveling. There was more than Rs.500 in my Paytm wallet when my Paytm issued fastag stopped working. I was travelling through successive toll gates. didn’t have a problem with the first 8 gates.. the next few gates showed my tag to be blacklisted. I tried topping with another 500, and waited for 30 minutes before passing through the next gate. the tag was blacklisted even after having 1000+ in my Paytm wallet. This was such a hassle as number of vehicles piled up after me. Raised a ticket with customer care.. waiting a to hear from them.. its been two days and no response from them yet.