Quick question.

It could be many things, such as; He checked it, unusual transaction amount or maybe there was a recent purchase by cardholder. My own card got blocked by my bank when i tried to do a transaction under £400 as i'd used it on a different computer/IP.

It will require trial and error tbh, keep trying till he succeeds.
 
Sometimes it happens. You just gotta charge it to the game. Checker could have killed it. Could be an unusual purchase amount. Could be a problem with ip. cvv could be wrong. Address could have changed.

Did he try the same site with a different card?

It will require trial and error tbh

This is the best advice you will get.
 
happened to me with halifax and Lloyds. Its doesnt pass vbv....
 
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