1.

It doesn't matter.

Because the bank doesn't care what you sign, you can even draw a circle. Most importantly, the signature of the merchant when accepting your card is consistent with the signature on the back of your card;

2.

Report the loss If you care that your signature doesn't match your usual signature, report the loss. Just sign the correct name on the reissued card after reporting the loss, but note that some banks will charge a loss reporting fee or a replacement fee.

3.

Don't use this credit card, hehe, wait until the expiration date (usually 2-3 years) and sign the correct name on the card reissued to you-this method is kuso's. ...