I have been using Paytm since 2015. It is too easy for use but there are several vulnerabilities which is observed by me as a user. The most important drawback of Paytm is when your payment gets failed then your money is not returned to your bank account, it returns to your Paytm wallet and if you want to transfer it in your account some money has deducted. Paytm has so many features but some of features has some issues like current Railway ticket booking is start after half hour latter than IRTC website , therefore most of the time ticket has not available on Paytm. It’s customer service is also very poor. So I suggest everyone to minimize the use of Paytm.