Mis-sold Life Insurance on Mortgage ?

When we took out our first Mortgage in 1990 it was for £20,000 and despite my protests that we had Life Insurance already which would have covered the Loan, and also we both received generous 'death in benefits' from our Employment, I was told by The Woolwich that we could not have the Mortgage without the Insurance. Therefore we were paying twice over for the same product. Our life insurances were with a different Insurance Company. Is their such a valid claim as Life Insurance against a Mortgage?

I now believe that this falls under a mis-sold policy. I would appreciate hearing from anyone who could advise or who have experienced the same.