very poor service recieved from automark melrose

on the 12/12/2014 morning I bought a car from automark Melrose, I pay them to put leather on my seats then they tell me to come back on the 15/12/2014 for collection. when I came back as promised there was no leather seats and all document that includes invoice, registration and number plate were not ready, they promise that all document will be sent via courier in three days the money will be deposited before the end of the week. I just took a car with permit and hope that they we will do as promised. After that I waited for two weeks and started to call the sales person by the name of Chris but in vain. I then move to his manager Mark Barnes again I received same bad service, he keep on sending me permits and tell me to pay he will refund my money. to date I have not receive and my invoice. EVERY TIME WHEN I CALLED THEN THEY PROMISE TO FIX IT AND COME BACK TO ME AND THEY NEVER DID. MANAGER KEEP ON BLAMING CHRIS BUT HE IS A MANAGER HE SUPPOSE TO SOLVE ISSUE NOT BLAMING OTHER. WHAT A BAD SERVICE.