Endownments policy.

We were advised when we took out our mortgage in 1987 that we would better taken a endownment policy out . Further down the years the endownment there was to be a shortfall with our policy. We cashed the policy in and changed our mortgage to a repayment. I Had a phone call from emcas who said that for a fee they could help us get a possible money back for the misselling of this policy. They said that if we won that we would only get 54% back they would take the rest. Is theer any information out there that we can try and do this ourselves

Thanks for you help