Jem, yes - which card is it?
When I had a Barclaycard they were very good about phoning me to alert me to unusual activity - my card had been cloned and used to buy building materials all around the UK, which they knew wasn't my usual pattern. How would they be waiting for you to contact them, if you didn't know about the fraudulent attempts? - it would have saved you that embarrassment if they contacted you straight away by phone or secure email. I take your point also, you could have been relying on that card for something vital. I would write a stiff letter to their Customer Services.