Why was credit card fraud so easy to commit?

My wife and I have Sainsbury’s Bank credit cards which we use for all our shopping, and typically pay between £700 and £900 a month to service the account. At the end of June the debit balance was just over £1,000.

When I checked my emails I was surprised to see one from Sainsbury’s Bank saying that it could not increase my credit limit to £20,000 but would do so to £14,500. That puzzled me, as I had not requested a higher credit limit. Online, I was astonished to see a balance transfer of £9,000, plus a 3% transaction fee

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