An approved cc transaction/payment cannot be cancelled. Call any bank and they will tell you the same.

Get the application form.
Supplementary card application will require the principle to also sign in the application form.

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Added on December 18, 2012, 2:02 pm

You need to raise a dispute with the bank. (To all noobs : dispute Dispute refers to a process and not a verb. Don't go quarreling with the bank)
Call the bank and you'll be asked to fill in a form along to provide with whatever evidence. (Note : Doesn't mean you have a police report, you are scot free) Bank will conduct their own internal investigation and this may take up to 3-4 months. If you are found not liable for the transaction (Remember this process is not automatic nor a police report is a ticket), the bank will execute "credit" / reversal for the transaction. No such thing as canceling the transaction.