Fees and charges triggered by mis-sold PPI premiums should be paid back, the Financial Ombudsman Service said after a BBC investigation claimed customers could have possibly been under-compensated by £1 billion.
Principal Ombudsman Caroline Wayman said: "If a fee is the result of the mis-sold PPI it should be given back, and if it's not included that would be a mistake."
She also recommended that credit card customers who fear their fees and charges were left out of compensation calculations approach their banks to discover what happened.
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