Sorry what do you mean by, Have HSBC default you for a bank charges related sum?

Hi i have sent letters to HSBC requesting the unlawful bank charges to be repaid to me, how ever i have received a letter from them saying that my claim will go on hold untill the Office of Fair Trading have agreed that the charges are unfair. Can they do this and is there any way that i can still claim the charges back? Do i now have to wait untill the Office of Fair Trading have agreed the charges are unafir? If anyone could give me some advise that would be great. Many thanks