IDFC Bank — IDFC bank Fastag account expired

I have IDFC bank fastag which is in use with sufficient balance.
The IDFC bank portal does not let me login as it shows that the account has expired. I want to recharge my account which is not available. The customer care dosent pick up call. There are no email addresses mentioned to which we can writer a complaint to resolve the matter.

Kindly help us through.
I am not going to mention my userid for security purposes.

Details will be provided directly to the bank customer executive who will service this complaint.