Because the bank basically won't ask for your ID number from the phone.

There are 7 digits behind the signature column of the credit card, the first 4 digits are the last 4 digits of your card number, and the last 3 digits are the security number (i.e. cvv2/cvc2/cvn2/cav2 code, etc.). ) for safety management. When you use your credit card for special transactions such as TV, telephone shopping and online shopping, the issuing bank is used to verify your identity.