I had a large number of improperly executed credit card agreements which I had been paying for 20 years.
After advice from CAG I decided not to make the remaining payments and they are all now statute barred.
Due to the length of the time I had the cards their will have been PPI payments made but...
1) Some credit cards were paid in full before I got into financial difficulty many years ago which I don't have records for.
2) Some accepted full and final settlement payments to clear the account,
3) Some accepted a final payment and marked as partially satisfied