ICICI Bank — Debit card is blocked for online transactions

I have been an icici customer since last 4 years.

But since the past few months the below mentioned problem started appearing always. I have never requested to block my debit card for any reason, nor have I ever entered the wrong cvv multiple times. But when I try to make online transactions, each time i get this message:

"for security reasons your verified by visa purchase has been prevented from being processed due to repeated entry of incorrect details. Your card/login has been blocked for online transactions at verified by visa merchants.

To unblock your card, please contact icici bank customer care."

I have tried calling customer care multiple times. Each time a computerized voice plays, asks me to enter my 16 digit card number which i would like to unblock, i enter it and it says my card is unblocked. But then when i try to do online transactions, it again says that my card is blocked for online transactions.

I have tried to unblock my debit card through the imobile app as well but it says my card is not blocked at all.

I am totally frustrated by now. Please help.

Regards,
Sayan