As an aside, I'd strongly advise trying everything possible to get your complaint resolved with the bank / credit company first before going to the Funancial Ombudsman. I know it sounds daft and obvious, but a lot of people complain, are unhappy their complaint has been rejected and then contact...
I work in an insurance complaints team and although I don't predominantly deal with PPI complaints, I still bloody hate dealing with them. So many people seem to think they had / have PPI when they didn't, or because they did have it assume it must have been mis-sold.
Best advice I can give is...