Peters Watersports
No registration paper with vehicle

I bought a vehicle cash from Peters Watersport World in 2012 (!!!) and still I haven't been given the registration paper! I eventually went to a lawyer, but no luck so far! I cannot even get a new licence disc from PWW - they just don' reply. Now I'm stuck with a vehicle which I've fully paid for, but cannot drive as the licence disc has expired. Does anybody have some good advice??