I have a IO mortgage with Halifax where the fixed rate lock ended about a year ago.. The terms of the mortgage were to be 2% over base rate at the end of the lock period. Right before it became a variable rate, they changed it to 3%. I checked my contract, which said they were allowed to do this if they sent a letter and offered me other products, which they never did. Countless calls and letters later, I decided to take my case to the Financial Ombudsman. It took a year, but today they sent a letter admitting that Halifax was in the wrong and they agreed to refund the difference.
I can say nothing good about the customer service and poor respose in the UK. It has been a pleasant suprise that the government's watchdog has stepped in to do the right thing. You have to be persistent as even the Ombudsman tried to close my case three times without a resolution.