Can somebody please advise me?

MBNA have told me that I have had PPI on my credit card since 1998 and I assume it is still going as I have not been told it was cancelled at any time.

I have received a letter today saying that they have upheld my complaint and are offering me a redress of £51 PPI and £405 total with interest.

This credit card has been running at a 30%+ interest rate and from around 2006 to 2014

the total debt has run at least 5000 per month.

Does a figure of £51 total PPI paid over 20 years at these figures seem realistic or should I go to the Ombudsman? As MBNA have said they will not enter into any correspondence I feel I have no choice