Banks are in crisis - and if you're one of the suckers to whom they lent pre-crunch money, it's your fault. But you'd think that in these leaner times they would make greater efforts to look after loyal customers with high incomes. You'd be wrong.

With no debts, a squeaky clean credit rating, savings and a high disposable income, I'm no risk. My bank of more than 20 years, Lloyds TSB, accepts that. Sadly, there's a glitch on the system with my name on it, highlighted in red.

Because of debts accrued at university ten years ago, I was demoted to a basic cash account, unable to use my cash-card at other banks or abroad (although I could use it in shops and on the internet).

I've had no debts and a good income for some years, yet the bank still won't upgrade me to a current account. As my cashflow improved, whenever I contacted my branch they asked where the money came from. Apparently satisfied that I wasn't laundering for some South American cartel, they then asked if I'd like an upgrade. When I said that would be lovely, I was told that I couldn't have one.

When I queried this lunacy I was advised to write to the bank's own complaints unit. Four months later, I've had no response. When I called to ask what was happening I was told that I would be called back that afternoon. I wasn't.

I'm not alone. Complaints to the Financial Ombudsman rose by a third from 2006-07 to 2007-08; around one complaint in five from the public to the Information Commissioner's Office (ICO) involves inaccurate data obtained by banks.

Much of this is held by the big credit agencies. A 2004 survey in the US found that 25 per cent of credit reports compiled by Experian, Equifax and Trans Union contained errors serious enough for customers to be denied credit.

Under the Data Protection Act, you have the right to know that information is accurate, up-to-date and kept no longer than necessary; to see personal information held about you and to correct it if it is wrong. If you believe your bank has false information, contact the ICO.

I've now moved my savings to a building society that is happy to give me the account I want, and I'm considering turning my trial separation from Lloyds into a divorce. It's not its refusal to upgrade my account that is the real problem: my complaint is their refusal to investigate my complaint. As the credit crunch reaches its first birthday, times are harder for banks and customers alike. Is it good business to alienate the very people who keep them in business?

Mark Piggott is a novelist

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