Answered on January 22,2020
You can cancel Paytm FASTag through 2 options.
Call on Toll-free number: 1800-102-6480 and mention your mobile number against which the tag has been registered along with the Vehicle Registration Number (VRN) or Tag ID. The customer support agent will get in touch with you to confirm the closure of FASTag.
The tag can also be suspended from the "Manage Tags" section in your FASTag sub-wallet.
The balance amount (if any) remaining in the related to FASTag would be returned to Customer in his Paytm Wallet.