I am sorry you've had trouble with your card, it's possible the card is faulty. I'm afraid we don't service customer accounts via email as it's not secure. If you're registered for online banking then you can log in at tescobank.com and request a replacement card. You can do this by following the below instructions;
Log in and click 'Manage account' > 'Manage your account' found on the left hand side then 'Get a replacement card'.