Old Mutual is not paying my pension funds for no r

These people are refusing to pay me my pension funds that my previous employer invested with them. They decided to pay me less than 1% of the total amount. They have also decided to stop replying to my emails and when ever I call someone will always tell me they will elevate the matter but nothing happenes. It is more than 5 month now. With such a very bad service am receiving from Old Mutual I refuse to have anything to do with Old Mutual in the future. What surprises me is that Old Mutual has been around for years I was not expecting this very bad service, I automatically thought that their systems have been perfected over the time they have been around