tried and failed

so, I tried to reclaim all the unfair charges applied to my credit card from 2005/06, which firstly caused me to go into debt. my cc was for £1000, back then I paid by cheque. so, the MBNA had a 7-day clearance. which made my payment late so I was charged £25 late payment fee. and £25 over limit fee.this was applied to my account for a fair few months making my account balance to roll out of control and I gave up I felt I was fighting a losing battle. so anyway not to drone on and on, and bore you all in all, after using martins calculator (what would we do without martin ) they owed me over £900 in over charges with interest the ombudsman decision was I should have known so, therefore I'm too late to claim I tried and failed